My first steps into python

Python is an interpreted, high-level, generale programming language

Python has a design philosophy that emphasizes code readability, notably using significant whitespace {wiki}

Python is a strongly typed language

Code sample :

Consells :

• limit all lines to a maximum of 79 characters

• quotes : always use single quote

• indenting : 4 spaces

  Code blocks : python requires indentation to indicate lines of code which belong together, as "begin" to "end" in Pascal

• comentaris : comments in python begin with a hash mark (#) and whitespace character and continue to the end of the line

• use a style convention - go here : PEP8

WhirlWinTour

En mi opinión es un lenguaje muy elegante. Para hacer programas sencillos es muy agradable de usar. Pero tiene un problema serio de portabilidad, por dos razones:

• La versión más extendida es la 2, pero hace ya muchos años que la 3 está disponible y tiene muchas mejoras con respecto a la 2. Por defecto en Linux viene python 2, y por eso cuesta sacárselo de encima.

• El sistema de librerías es un infierno: las dependencias se almacenan de forma global, no en cada proyecto.
  Cualquier proyecto que no sea de juguete requiere librerías externas. Si un proyecto usa una versión de una librería y otro usa otra, entran en conflicto. Descargar una nueva versión de una librería puede hacer que dejen de funcionar un montón de herramienta que usas en Linux y no sabías que funcionaban con python.

Para arreglar este problema hay docenas de workarounds que requieren que el developer tenga que aprender la gestión de "entornos aislados" y cosas por el estilo. Esto es asumible para un developer voluntarioso, pero si quieres que tu código pueda ser usado por otros, les vas a obligar a tener que aprender a usar esos mecanismos de workaround para que también les funcione a ellos.

It is highly recommended that you use python virtual environments, or venvs.

A venv is an isolated copy of the python executable and associated files, which provides a separate environment for installing python modules, independent from the system python installation. You can have as many venvs as you need, which means that you can have multiple module configurations set up, and you can switch between them easily.

Read realpython intro

Another project :

1. create a new directory for your project and navigate into it.
2. set up a virtual environment for Python dependencies:
   python3 -m venv venv source venv/bin/activate
3. install Flask and Flask components :
   pip install Flask Flask-SQLAlchemy Flask-Login flask-wtf email_validator

Flask

In many programming languages, variables are best thought of as containers or buckets into which you put data.

In Python, by contrast, variables are best thought of not as containers but as pointers.
one consequence of this: because Python variables just point to various objects, there is no need to "declare" the variable, or even require the variable to always point to information of the same type!

There is a consequence of this "variable as pointer" approach that you need to be aware of. If we have two variable names pointing to the same mutable object, then changing one will change the other as well!

WhirlWindTour ch.03

Python's simple types are summarized in the following table:

Python also has several built-in compound types, which act as containers for other types. These compound types are:

WhirlWindTour ch.06

Modules and packages are two mechanisms that facilitate modular programming.

Any python file is a module, its name being the file's base name without the .py extension.
A package is a collection of python modules: while a module is a single python file, a package is a directory of python modules containing an additional __init__.py file.

stack overflow

A package or module name can *not* start with a number - stackoverflow - it will trigger a SyntaxError

There are three different ways to define a module in python:

• a module can be written in python itself.
• a module can be written in C and loaded dynamically at run-time, like the re (regular expression) module.
• a built-in module is intrinsically contained in the interpreter, like the itertools module.

real python modules and packages {***}

A module is a simple python file that contains collections of functions and global variables and with having a .py extension file.

A package is a directory having python modules and also having a __init__.py file.

geeks 4 geeks

"dir(module)" returns the names of the attributes of the "module" (list of methods, properties and submodules)

dir() does not list the names of built-in functions and variables.
If you want a list of those, they are defined in the standard module builtins:

For all the details of a module, try "help(module_name)"

A module is a file containing python definitions and statements. The file name is the module name with the suffix .py appended. The definitions from a module can be imported into other modules or into the main module.

The statement

... does not enter the names of the functions in the current symbol table ; it only enters the module name.

Using the module name you can access the functions :

If you intend to use a function often you can assign it a local name :

There is a variant of the import statement that imports names from a module directly into the importing module’s symbol table.

This does not introduce the module name from which the imports are taken in the local symbol table, so in the example, fibo is not defined.

If the module name is followed by as, then the name following as is bound directly to the imported module.

This is effectively importing the module in the same way that import fibo will do, with the only difference of it being available as fibi.

It can also be used when using from with similar effects:

The important one for me is :

Let’s take a look at what happens when python executes the statement:

When the interpreter executes the above import statement, it searches for mod.py in a list of directories assembled from the following sources:

• The directory from which the input script was run or the current directory if the interpreter is being run interactively
• The list of directories contained in the PYTHONPATH environment variable, if it is set. (The format for PYTHONPATH is OS-dependent but should mimic the PATH environment variable.)
• An installation-dependent list of directories configured at the time Python is installed

The resulting search path is accessible in the Python variable sys.path, which is obtained from a module named sys:

Goal : we want to have some config values in a file, included in .gitignore

1. in main progarm "bot.py", we code
   import config # config.py holds bot token as "bot_token"

2. we specify the configuration values :
   nicolau@mars:~/sebas/python/telegram/telegram.ext/smokey$ cat config.py bot_token='1234567890:AABBCCDDEEffggxQYV3wQqDLL8zNfrJwPot'

3. finally we use them in main code (bot.py)
   nicolau@mars:~/sebas/python/telegram/telegram.ext/smokey$ cat bot.py updater = Updater( config.bot_token, workers=10, use_context=True )

Al fitxer arrel, posem :

I al directori hi tenim :

Ara al fitxer principal podem fer servir les funcions implementades :

... a package is a directory of python modules containing an additional __init__.py file (even empty)

real python {***}

I have one py that finds RF24 and another that does not

We could have

Anem al directori i fem

As :

The package must be one directory bellow your code :

Gracies, Albert !

I el seu contingut :

Comprovem importacio :

Com el fem servir ?

{20220806} Has de copiar tots els teus moduls al directori de llibreries de python, al subdirectory que mes t'agradi exemple "sebas".
Llavors podras fer un "import sebas" des de qualsevol python.

1. ens aclarim amb quin python treballem i el seu directori :
   pi@pi0:~ $ python3 Python 3.7.3 (default, Jan 22 2021, 20:04:44) >>> import sys >>> sys.path ['', '/usr/lib/python37.zip', '/usr/lib/python3.7', ...

2. hi fem un directori per les nostres eines :
   pi@pi0:/usr/lib/python3.7 $ sudo mkdir sebas_eines

3. fem que sigui un package :
   pi@pi0:/usr/lib/python3.7 $ sudo touch sebas_eines/__init__.py pi@pi0:/usr/lib/python3.7/sebas_eines $ ls 0 -rw-r--r-- 1 root root 0 Aug 6 11:46 __init__.py

4. fem proves de "import" :
   pi@pi0:~ $ python3 Python 3.7.3 (default, Jan 22 2021, 20:04:44) [GCC 8.3.0] on linux Type "help", "copyright", "credits" or "license" for more information. >>> import sebas_eines

5. codifiquem un servei :
   pi@pi0:/usr/lib/python3.7/sebas_eines $ cat greeting.py def say_hello(name: str) -> str: return f'Hello {name}!'

6. codifiquem un client :
   pi@pi0:~/python/proves $ cat mestre.py #!/bin/python3 from sebas_eines import greeting rc = greeting.say_hello("Sebas") print( rc )

7. verifiquem q funciona :
   pi@pi0:~/python/proves $ ./mestre.py Hello Sebas!

When you run a python module with ( url )

... the code in the module will be executed, just as if you imported it, but with the "__name__" set to "__main__".

That means that by adding this code at the end of your module:

... you can make the file usable as a script as well as an importable module, because the code that parses the command line only runs if the module is executed as the “main” file

Again : the __name__ test at the bottom is true only when this file is run as a top-level script (e.g., from a command line, via an icon click, or within the IDLE GUI), not when it is imported.

There is no "standard" way :

from here :

A bit better :

Sembla que amb la versio 2.7 podem fer servir requests.exceptions.HTTPError ...

Revisem la documentacio !

We can use importlib.metadata since python 3.8 :

Yep ! Went into importlib_metadata

• self

  The word 'self' is used to represent the instance of a class. By using the "self" keyword we access the attributes and methods of the class in python.

• __init__ method

  "__init__" is a reserved method in python classes. It is called as a constructor in object oriented terminology.
  This method is called when an object is created from a class and it allows the class to initialize the attributes of the class.

url

Lets have "main" file demo.py :

The secondary file is tplight.py :

Very few :

• "print" statement
  The print statement has been replaced with a print() function - details
• libraries - old libraries built for python 2 are not forward compatible
  But new libraries are created strictly for python 3
• strings are stored : ASCII (v2) or Unicode (v3)
• division : v2 rounds down (by default), v3 does not round

python.org docs, url

• //pi0/home/sebas/python/mostrar_temperatura.py
  old code
  import commands # tempgpu = commands.getoutput('/opt/vc/bin/vcgencmd measure_temp' ).replace('temp=', '' )
  
  new code
  from subprocess import check_output tempgpu = check_output(["vcgencmd","measure_temp"]).decode()

From an improved string formatting syntax Guide :

f-strings are expressions evaluated at runtime rather than constant values !

If we want to provide formatting information :

zetcode : width, justify, numeric notations,

python 3.x makes a clear distinction between the types:

• str = '...' literals = a sequence of Unicode characters (UTF-16 or UTF-32, depending on how python was compiled)
• bytes = b'...' literals = a sequence of octets (integers between 0 and 255)

Bytes literals are always prefixed with 'b' or 'B'; they produce an instance of the bytes type instead of the str type.

You use "str" when you want to represent text.
You use "bytes" when you want to represent low-level binary data like structs.

You can encode a str to a bytes object :

And you can decode a bytes into a str :

docs.python.org

Python 2 uses two different types for strings, unicode and str.

When you define a literal string the interpreter actually creates a new object of type str that holds this literal.

You can explicitly define a literal string as unicode using the u prefix.

The interpreter will create instead a unicode object for this literal.

For ASCII text, using str type is sufficient but if you intend to manipulate non-ASCII text it is important to use unicode type for character level operations to work correctly.

stackoverflow

docs.python {****}

Some python packages can be found in the Raspbian archives, and can be installed using apt, for example:

Not all python packages are available in the Raspbian archives, and those that are can sometimes be out of date. If you can't find a suitable version in the Raspbian archives, you can install packages from the Python Package Index (known as PyPI).

To do so, install pip:

Then install python packages (e.g. simplejson) with pip3:

It is also easy to remove them :

And to list the installed packages :

Sometimes we need to upgrade a package :

Sometimes, if you dont use "sudo", you get this ugly message :

Also on install :

If you want to run the service as root, you have to install the module with sudo: sudo python3 -m pip install my_module

Personal Package Archives (PPAs) are software repositories designed for Ubuntu users and are easier to install than other third-party repositories.

• Dont run pip under "sudo" !

  url : when you run pip with sudo, you run setup.py with sudo, so you run arbitrary python code from the internet as root

• Always launch it from python :
  $ python -m pip install <package name>

• install a specific version :
  nicolau@mars:~$ python -m pip install pyqt5==5.15.1

• install requirements in a file :
  nicolau@mars:~$ python -m pip install -r requirements.txt nicolau@mars:~$ cat requirements.txt PyQt5==5.15.1 tuyapy==0.1.3 requests==2.24.0

• verify your installation :
  nicolau@mars:~$ python -m pip check launchpadlib 1.10.6 requires testresources, which is not installed. telebot 0.0.3 has requirement requests==2.7.0, but you have requests 2.24.0.

The correct form is

Si pip ja apunta a python3 llavors podem

Per comprovar on apunta pip :

[20160604] Install under W2008R2 at W500.

Compte : instalar python v2 : 2.7.11 - normal "Windows x86 MSI installer"

Llegir Using Windows

Resultat :

If a name.py code contains a "import" sentence, this "code.py" must be at this directory : "c:\python27\lib"

You can install a module using "c:\python27\scripts\pip install modulename"

Lets update "pip" :

Lets visit "pyping" again :

Use pyping sample.

Read about installing software in python

First steps

In my Raspberry we have :

How does linux know which one to use ?

To change it, use

I've done :

• python -m pip install psutil - display CPU use, etc
• sudo pip3 install psutil - python v3

Version we have :

Problems and solutions :

• speedtest : update
• pip : sudo apt-get install python3-pip
• numpy - ModuleNotFoundError: No module named 'numpy'
  python -m pip install --upgrade numpy
• cv2 - ModuleNotFoundError: No module named 'cv2' : sudo pip install opencv-python
  url : python -m pip install opencv-python

We do it on :

• 202006 - MARS/Ubuntu
  nicolau@mars:~$ python --version Python 3.6.9

  20201204 - we need "python-kasa", which requires "Python >=3.7, <4.0"

  1. update whole system
     nicolau@mars:~$ sudo apt update -y

  2. install v 3.7
     nicolau@mars:~$ sudo apt install python3.7

  3. add python 3.6 & python 3.7 to update-alternatives
     $ sudo update-alternatives --install /usr/bin/python3 python3 /usr/bin/python3.6 1 update-alternatives: using /usr/bin/python3.6 to provide /usr/bin/python3 (python3) in auto mode $ sudo update-alternatives --install /usr/bin/python3 python3 /usr/bin/python3.7 2 update-alternatives: using /usr/bin/python3.7 to provide /usr/bin/python3 (python3) in auto mode

  4. update python 3 to point to python 3.7
     nicolau@mars:~$ sudo update-alternatives --config python3 There are 2 choices for the alternative python3 (providing /usr/bin/python3). Selection Path Priority Status ------------------------------------------------------------ * 0 /usr/bin/python3.7 2 auto mode 1 /usr/bin/python3.6 1 manual mode 2 /usr/bin/python3.7 2 manual mode Press <enter> to keep the current choice[*], or type selection number:

  5. display actual version :
     nicolau@mars:~$ python --version Python 3.7.5

  url

  "llegir_preu_electre.py" li cal v 3.7+ (see)

  nicolau@mars:~$ which python /usr/bin/python nicolau@mars:~$ ls -al /usr/bin/python 0 lrwxrwxrwx 1 root root 16 May 11 2020 /usr/bin/python -> /usr/bin/python3 nicolau@mars:~$ ls -al /usr/bin/python3 0 lrwxrwxrwx 1 root root 25 Dec 4 2020 /usr/bin/python3 -> /etc/alternatives/python3 nicolau@mars:~$ ls -al /etc/alternatives/python3 0 lrwxrwxrwx 1 root root 18 Jan 31 13:39 /etc/alternatives/python3 -> /usr/bin/python3.7

  Compte : python 3.7 breaks apt-get : solution

  Now we come up with a very interesting problem : "term" does no open

  "syslog" has a message like

  nicolau@mars:~$ cat /var/log/syslog ImportError: cannot import name '_gi' from 'gi' (/usr/lib/python3/dist-packages/gi/__init__.py)

  Solution (can't open a Terminal !) :

  1. navegar pel filesystem "grafic" i picar en qualsevol carpeta "Open in Terminal"
  2. corregir
     sudo gedit /usr/bin/gnome-terminal ... change #!/usr/bin/python3 to #!/usr/bin/python3.6

  Another problem : red circle with a white minus sign in the toolbar + "A problem occurred when checking for the updates"

  sudo update-alternatives --config python3
  1. set it to 3.6
  2. use "/usr/bin/python3.7" in your code
     nicolau@mars:~/sebas/python/smart_plug$ cat plug_power.py #!/usr/bin/python3.7 sebas@minie:~/dades/python/smart_devices$ more 1_plug_power.py #!/usr/bin/python3

• 20200710 - R3 - go 3.7 :

  • download and extract
    pi@ai-pi:~ $ sudo su root@ai-pi:/home/pi# cd /usr/src root@ai-pi:/usr/src# wget https://www.python.org/ftp/python/3.7.0/Python-3.7.0.tgz root@ai-pi:/usr/src# tar -xf Python-3.7.0.tgz

  • install dependencies
    sudo apt-get update sudo apt-get install -y build-essential tk-dev libncurses5-dev libncursesw5-dev libreadline6-dev libdb5.3-dev libgdbm-dev libsqlite3-dev libssl-dev libbz2-dev libexpat1-dev liblzma-dev zlib1g-dev libffi-dev

  • configure and install python3 :
    root@ai-pi:/usr/src# cd /usr/src/Python-3.7.0 root@ai-pi:/usr/src/Python-3.7.0# ./configure --enable-optimizations { *** wow *** } root@ai-pi:/usr/src/Python-3.7.0# make altinstall { *** wow wow 15 min *** }

  • update the links
    root@ai-pi:/usr/src# ln -s /usr/local/bin/python3.7 /usr/local/bin/python3

  • edit "/usr/bin/lsb_release" to have "#!/usr/bin/python2.7"

  • verify versions
    root@odin:~# python --version Python 3.4.2 root@odin:~# python3 --version Python 3.7.0 sag@odin:/usr/local/bin $ pip3.7 -V pip 10.0.1 from /usr/local/lib/python3.7/site-packages/pip (python 3.7) sag@odin:~ $ pkg-config --libs openssl -lssl -lcrypto sag@odin:~ $ apt list *certi* Listing... Done ca-certificates/oldstable,now 20200601~deb9u1 all [installed] ca-certificates-java/oldstable 20170929~deb9u3 all ca-certificates-mono/oldstable,now 4.6.2.7+dfsg-1 all [installed,automatic] fusiondirectory-plugin-certificates/oldstable 1.0.19-1+deb9u1 all python-certifi/oldstable 2016.2.28-1 all python3-certifi/oldstable 2016.2.28-1 all ruby-certificate-authority/oldstable 0.2.0~6dd483bf-1 all xul-ext-certificatepatrol/oldstable 2.0.14-5 all

    You can revert back to the default python 3 version anytime by simply updating the link created above. Also keep in mind updating raspbian will likely break this and you may have to recreate the links if needed.

    20201110, R3 - go back to v 3.5

    sag@odin:/usr/bin $ sudo rm /usr/local/bin/python3 sag@odin:/usr/bin $ which python3 /usr/bin/python3 sag@odin:/usr/bin $ python3 -V -bash: /usr/local/bin/python3: No such file or directory ln -s /usr/bin/python3 /usr/local/bin/python3 sag@odin:~ $ python3 -V Python 3.5.3

  • sudo apt install libssl-dev libncurses5-dev libsqlite3-dev libreadline-dev libtk8.5 libgdm-dev libdb4o-cil-dev libpcap-dev

  • sudo apt-get install python3.5 : "Unable to locate package python3.5"

• 20201025 - R0 - url :
  sebas@pi0alby:~ $ sudo apt-get update $ sudo apt install python3 idle3 $ sudo apt autoremove $ sudo apt install python3-pip sebas@pi0alby:~ $ python -V Python 2.7.16 sebas@pi0alby:~ $ python3 -V Python 3.7.3

  Cridem a "python3" explicitament en el codi !

  Instalem pip3 amb "python3 -m pip install --upgrade pip"

  Instalem mitjançant pip3 install --user <package_name>

On almost any install using pip3 or python3 (requests on R3), I get :

OpenSSL versions are :

After moving back from 3.7 to 3.5 (see above), ssl works fine :

*** Cant use rrdtool with python3 ***
why ?

Here we find

Note: unless binary versions are available for your target system, the command above requires rrdtool development files (headers, libraries, dependencies) to be installed.

See python-rrdtool

A shebang line defines where the interpreter is located

SheBang is ignored if we use this form :

The general form ...

... executes whatever python is on the users $PATH. This form is resilient to the python interpreter being moved around, which makes it somewhat more portable, but it also means that the user can override the standard python interpreter by putting something ahead of it in $PATH. Depending on your goals, this behavior may or may not be OK.

The specific form ...

... deals with the common case that a python interpreter is installed in /usr/bin. If it's installed somewhere else, you lose. But this is a good way to ensure you get exactly the version you want or else nothing at all ("fail-stop" behavior).

stackoverflow

The most specific form ...

... forces to work with version 3, installed on a specific path {mychoice}

You can use

...for portability across different systems in case they have the language interpreter installed in different locations.

encoding declarations

Ens dona :

Or maybe

More complete :

Complete code with exceptions

Some simple parameters :

There are "non-keyword" parameters, and there are "keyword" parameters.

They have to be in that order, or you get a error message like this :

python allows function arguments to have default values. If the function is called without the argument, the argument gets its default value.

Default values indicate that the function argument will take that value if no argument value is passed during the function call.

The default value is assigned by using the assignment(=) operator of the form keywordname=value.

/ is regular division (returns float) and // is floor division (returns int).
Floor division was introduced in python 3.

right-justify and fill with char - w3schools :

docs.python :

• line.split() - split into parts
• line.strip() - remove leading ...

Generally, double quotes are used for string representation and single quotes are used for regular expressions, dict keys or SQL - geeks 4 geeks

Double quotes around a string are used to specify a regular expression search - ks.uiuc

When a string contains special characters like quotes, we need to escape them :

You can put a backslash character followed by a quote (\" or \'). This is called an escape sequence and python will remove the backslash, and put just the quote in the string.

We can use triple quotes (i.e., triplet of single quotes or triplet double quotes) to represent the strings containing both single and double quotes to eliminate the need of escaping any :

A pending improvement : template strings

Compte : removed backticks in python 3 !

Les cometes han de ser senzilles - si les posem dobles, tenim :

We can define some code to be used few times

easy python docs

A python function will always have a return value. That default return value will always be None.

real python

To display all environment, do :

To read an environment variable from python, use os.environ :

library

Compte : "HOSTNAME" is NOT an envir var ! pubs.opengroup

Get it from "socket" :

Define it in "/etc/environment" and reboot :

Cant "export" it :

Verify it is visible :

Use "os" :

Aware of errors, "None" versus "KeyError" :

Lets improve the code with a "try" sentence :

From a service, /etc/environment is no used.

So, we use EnvironmentFile [***]

Display your log lines using journalctl

sys.exc_info docu

Un molt bon article de linuxjournal.com/article/5821 : sys.exc_info() function

Un altre StackOverflow :

Code from linuxjournal.com/article/5821 !!!

Exceptions are used to handle errors and other exceptional conditions that may occur during program execution.

Catching Any Exception:

See exception hierarchy and KeyError

wiki :

A more complete example is :

Nice code :

linuxize

A bit more could be :

Complete one :

GPT says "basic syntax of exception handling"

A larger one :

be careful with catching the subclass of errors before their superclass. In your example, this would mean putting HTTPError before URLError. Otherwise, the subclass will never get caught.

The last except clause may omit the exception name(s), to serve as a wildcard :

errors

Another source :

• in the event of a network problem (e.g. DNS failure, refused connection, etc), Requests will raise a ConnectionError exception.
• in the event of the rare invalid HTTP response, Requests will raise an HTTPError exception.
• if a request times out, a Timeout exception is raised.
• if a request exceeds the configured number of maximum redirections, a TooManyRedirects exception is raised.
• all exceptions that Requests explicitly raises inherit from requests.exceptions.RequestException.

You can either catch the base-class exception, which will handle all cases :

Or you can catch them separately and do different things :

read the docs - requests errors and exceptions

No puc treure els detalls de un "Name Error" : docs.python , airbrake

Tampoc de un "TypeError" - code

stacloverflow

In my_main() we can get this error message :

Then, we have to code :

And now we can see the real cause of the error :

Resum : faltava "import psutil"

"complete hierarchy" from here from here

Python has no command for declaring a variable. A variable is created the moment you first assign a value to it.

Result is {0-6} or {6-6} depending on the presence of the {***} sentence

logging basics

logging to a file

En lloc de fer "print()", cridem al nostre codi per afegir marca temporal :

atexit - this only works with functions that can be called without arguments.

Poso una "ç" en un comentari i surt :

Llegim http://python.org/dev/peps/pep-0263/

The complete form is :

A short form in one line is :

I use a lot :

You can put few statements in one line :

In python, you can have if-else statements on one line, using the conditional expression syntax:

codingem

A compound if statement is written like this :

A simple loop is :

A "forever" loop is like this :

In python 3, print() is a function

Syntax is (few samples) :

Mind that the "print(" initial parentheses has to be closed at the very end of line, after the "% (params)"

Lots of print format tricks :

The %s specifier converts the object using str(), and %r converts it using repr() - url

pass statement

El as es per fer un alias, i que no hagis de canviar totes les referencies en cas que canviis la llibreria. Molt util per saltar de versions.

Pero de cop ara ets el sebastianot oi?

Compte : "old" name is not valid anymore, so we can find this error :

A "bytes" object represents a sequence of bytes, a "string" object represents a sequence of unicode code points.

To convert between from "bytes" to "string" and from "string" back to "bytes" you use the bytes.encode and string.decode functions. These functions take two parameters, an encoding and an error handling policy.

"itertools" or this

There are four collection data types in the python programming language:

• list is a collection which is ordered and changeable. Allows duplicate members.
  Square brackets : thislist = [ "apple", "banana", "cherry" ]
  You can use the list as an array.

• tuple is a collection which is ordered and unchangeable. Allows duplicate members.
  Round brackets : thistuple = ( "apple", "banana", "cherry" )

• set is a collection which is unordered and unindexed. No duplicate members.
  Curly brackets : thisset = { "apple", "banana", "cherry" }

• dictionary is a collection which is unordered, changeable and indexed. No duplicate members. Have keys and values.
  Curly brackets : thisdict = { "brand": "Ford", "model": "Mustang", "year": 1964 }

w3 schools

Use type() function to print the data type of a var :

In python programming, key-value pairs are dictionary objects and ordered list are list objects.

Brief refresher on the techniques used to extract data from a JSON structure.

A list is a collection which is ordered and changeable. In python lists are written with square brackets.

Each item in the list has a value (color name) and an index (its position in the list). Python uses zero-based indexing.

Print all items in the list :

Print all items by referring to their index number:

Print all items, using a while loop to go through all the index numbers

A tuple is a collection which is ordered and unchangeable. In python tuples are written with round brackets.

A real sample :

A set is a collection which is unordered and unindexed. In python sets are written with curly brackets.

The reason the set iteration order changes from run-to-run appears to be because Python uses hash seed randomization by default. stackOverflow

educative.io

programiz

A dictionary is a collection which is unordered, changeable and indexed. In python dictionaries are written with curly brackets, and they have keys and values.

Keys inside a python dictionary can only be of a type that is immutable.

Immutable data types in python are integers, strings, tuples, floating point numbers, and Booleans.

Dictionary keys cannot be of a type that is mutable, such as sets, lists, or dictionaries.

When it comes to values inside a python dictionary there are no restrictions.

Another thing to note about the differences between keys and values in python dictionaries, is the fact that keys are unique. This means that a key can only appear once in the dictionary, whereas there can be duplicate values.

freecodecamp

You can change the value of a specific item by referring to its key name:

You can loop through a dictionary by using a for loop.
When looping through a dictionary, the return value are the keys of the dictionary, but there are methods to return the values as well.

Some details : url

geeks

Have to create a "shadow" copy not to get "RuntimeError: dictionary changed size during iteration" :

bobby hadz

Sorting a python dictionary: values, keys and more

Simple way :

Complete :

Elegant :

Another :

Working with : CSV, JSON

adam smith.haus

parse a string

See split CSV

If it's always going to be an even LHS/RHS split, you can also use the partition method that's built into strings.
It returns a 3-tuple as (LHS, separator, RHS) if the separator is found, and (original_string, '', '') if the separator wasn't present:

and/or

STACKOVERFLOW

Another sample :

stackOverflow

PEP8 is the officially suggested convention for code style.

The most widely used style guide in Python is known as PEP8, and can be found at https://www.python.org/dev/peps/pep-0008/

• both variable and function names should be lowercase where different words are separated by an underscore
  my_variable = 5 def my_function(a, b): return a + b

• If a variable is intended to be constant throughout the program, then you can write it in uppercase to indicate this:
  MY_NONCHANGING_VARIABLE = 5

• For classes, their names should be written with capitalized words joined together :
  class MyAwesomeClass():

Nice article

Use python -m pdb <program name> to go step-by-step thru your program.

Complete documentation

Basic debug commands :

• use "n" to execute actual line and stop at next line - skip subroutine
• use "s" to execute actual line and stop at first possible occasion - go into subroutine
• use "q" to quit program.

Insert "breakpoint()" to enter debug - realpython

doc.python.org {amb programmatic interface}, pymotw.com

Here's a list of resources to get started with the python debugger:

• Read Steve Ferb's article Debugging in Python
• Watch Eric Holscher's screencast Using pdb, the Python Debugger
• Read Ayman Hourieh's article Python Debugging Techniques
• Read the Python documentation for pdb - The Python Debugger
• Read Chapter 9 - When You Don't Even Know What to Log: Using Debuggers-of Karen Tracey's Django 1.1 Testing and Debugging

Display built-in functions, methods, modules and module attributes.

Problema 20210227 :

Solucio - posar com a segona linia el seguent :

A function is a block of organized, reusable code that is used to perform a single, related action. Functions provide better modularity for your application and a high degree of code reusing.

All parameters (arguments) in the python language are passed by reference.

tutorials point , code mentor

See r/w JSON sample

Often when defining a function, there are certain values that we want the function to use most of the time, but we'd also like to give the user some flexibility. In this case, we can use default values for arguments.

The values can also be specified by name if desired, in which case the order of the named values does not matter.

Another way of defining short, one-off functions

This lambda function is roughly equivalent to

So why would you ever want to use such a thing? Primarily, it comes down to the fact that everything is an object in Python, even functions themselves! That means that functions can be passed as arguments to functions.

WhirlWindTour ch.08

We shall use subprocess :

gist

Another sample :

Remember to convert the args to string before passing, using str(arg).

This can be used to pass as many arguments as desired:

I recommend using list as arguments like

StackOverflow

Shell scripts for system monitoring from here

Read datetime docu

strftime
The strftime() method returns a string representing date and time using date, time or datetime object.

strptime
The strptime() method creates a datetime object from the given string.

We can split it into separated values :

And improve it a bit :

In python, dates are objects. Therefore, when you manipulate them, you manipulate objects, not strings, not timestamps nor anything.

Any object in python have TWO string representations:

• the regular representation that is used by "print", can be get using the str() function.
  It is most of the time the most common human readable format and is used to ease display.
  So str(datetime.datetime(2008, 11, 22, 19, 53, 42)) gives you '2008-11-22 19:53:42'.

• the alternative representation that is used to represent the object nature (as a data).
  It can be get using the repr() function and is handy to know what kind of data your manipulating while you are developing or debugging.
  So repr(datetime.datetime(2008, 11, 22, 19, 53, 42)) gives you 'datetime.datetime(2008, 11, 22, 19, 53, 42)'.

saltycrane

pynative

You execute a python code from bash like this

And to access these arguments in python you can use:

The python results have to be available to bash :

Lots of ways and details, and python-shell module and API

Working sample - the python code ( after "npm install python-shell" )

And the result is :

On ho faig servir (gracies, Albert) :

• //odin/home/sag/express-sendfile/server.js crida "fer_foto.py"
• //odin/home/pi/semafor/1_sem.js crida "2_foto.py"
• //r0/home/pi/njs/fronius/servidor.js crida "3_ramon.py"

The server.py shall be like this

And we can call it like this :

To know the version we have :

Lots of uses

pandas is a Python package providing fast, flexible, and expressive data structures designed to make working with “relational” or “labeled” data both easy and intuitive.

pandas doc, options

10 minutes intro

Consider Results, an elegant and simple HTTP library for python, built for human beings.

TCP/IP :

• wireshark + la opcio "follow stream" per veure seguir el que es parlen
• python "requests" estirant del "payload" , o be alguna de les mil llibreries tcp/ip / arp, depen de on es trobi el dialeg que vols "destripar":

TCP

pibcast-1.0.tar.gz

geeks -> es un script !

To get TCP/IP local info into python we use :

There is a simple way to get the IP :

Explicacion en "man hostname" :

-I, --all-ip-addresses
Display all network addresses of the host. This option enumerates all configured addresses on all network interfaces. The loopback interface and IPv6 link-local addresses are omitted. Contrary to option -i, this option does not depend on name resolution. Do not make any assumptions about the order of the output.

El resultat es :

icmplib at github

Use it like this :

STORLINES vs STORBINARY

Lets compare "requests" to "urlopen"

A complete JSON info, as geolocation
homepage , including how to get external IP using 21 languages, as Lua, nim, jQuery, Scala ...

requests is requests : HTTP for Humans - see docu advanced section

Minimum code :

Have to add some code to manage errors and exceptions or timeouts

See code at TG.HTM

reddit

The same code has to be changed a bit, and I still dont know why : {p2 versus p3 ?}

urllib2 — extensible library for opening URLs - better known exceptions !

urllib2 provides some extra functionality, namely the urlopen() function can allow you to specify headers

docs.python.org : v 2, v 3

no funciona amb python3

The urllib2 module has been split across several modules in python 3 named urllib.request and urllib.error - python 3.8 , urllib

stack overrun

urllib2 is the name of the library included in Python 2. You can use the urllib.request library included with Python 3, instead. url

Alternatively, install the requests library for a higher-level and easier to use API. It'll work on both Python 2 and 3

Requests: HTTP for Humans

Homepage, API docu

requests will work on both Python 2 and 3

Quickstart, advanced documentation

Here is a complete sample :

In the event of a network problem (e.g. DNS failure, refused connection, etc), Requests will raise a ConnectionError exception

Response.raise_for_status() will raise an HTTPError if the HTTP request returned an unsuccessful status code

If a request times out, a Timeout exception is raised

If a request exceeds the configured number of maximum redirections, a TooManyRedirects exception is raised

All exceptions that Requests explicitly raises inherit from requests.exceptions.RequestException

Parameters to the GET request, as "h=1" : {url} : "URL&h=1"

The GET request expects sid and key while the POST expects X-Pvoutput-SystemId and X-Pvoutput-ApiKey. forum

To set HTTP headres, use "-H" : curl -H "X-Header: value" https://www.keycdn.com

Otherwise, use sid and key keywords :

Download historical solar photovoltaic data from PVOutput.org : python code

REST stands for "representational state transfer" and is a software architecture style that defines a pattern for client and server communications over a network.

REST defines the following architectural constraints:

• stateless: The server won’t maintain any state between requests from the client.
• client-server: The client and server must be decoupled from each other, allowing each to develop independently.
• cacheable: The data retrieved from the server should be cacheable either by the client or by the server.
• uniform interface: The server will provide a uniform interface for accessing resources without defining their representation.
• layered system: The client may access the resources on the server indirectly through other layers such as a proxy or load balancer.
• code on demand (optional): The server may transfer code to the client that it can run, such as JavaScript for a single-page application.

realpython -> "Flask", "Django REST Framework", "FastAPI"

{Albert, 20241223} - bottlepy

REST APIs listen for HTTP methods like GET, POST, and DELETE to know which operations to perform on the web service’s resources.
A resource is any data available in the web service that can be accessed and manipulated with HTTP requests to the REST API.
The HTTP method tells the API which action to perform on the resource.

CRUD operations to HTTP methods :

• GET retrieves resources
• POST submits new data to the server
• PUT updates existing data
• DELETE removes data

For example, here’s one of the URLs for GitHub’s REST API :

This URL allows you to access information about a specific GitHub user.

Un altre exemple :

This curl command has some options that are helpful to know :

• -i include the HTTP response headers in the output
• -X sets the HTTP method for the request
• -H adds an HTTP header to the request
• -d defines the request data

Mind Best practices for REST API security: Authentication and authorization

Un servidor de requeriments REST em sembla que ens empeny directament a nodeJS i Express

simplest python socket example, server side:

Or you can use HTTPServer module alongwith SimpleHTTPRequestHandler to create a simple webserver that serves your GET and POST request

Input : "write a minimal REST server in python, request is pure text "
This version of the server is designed to receive and process plain text data sent in the body of a POST request.

Output :

Details :

Lets run it :

The client is written in bsh and can be found here

crec recordar que era ... socket() + bind() + listen() + recv()

• JeffreytheCoder : Simple-HTTP-Server - dev.to & github
  When a client connects, the server accepts the connection and creates a new thread to handle the client's HTTP request. This way, the server can handle multiple clients concurrently.
• simple web server with C programming , uses "fork()"

• How to Build an API {***}

• wiki REST + architectural_constraints (to be RESTful)

Si no vols que tota la màquina passi per la VPN, sinó només el teu programa, pots utilitzar un Proxy SOCKS5. Molts serveis de VPN ofereixen aquesta opció. Pots fer servir una eina anomenada proxychains.

• instal·lació: sudo apt install proxychains
• configuració: edita /etc/proxychains.conf per afegir la IP i el port del proxy de la teva VPN.
• ús: executes el teu script així: proxychains python3 el_teu_script.py

Estatics :

On trobar-ne més en temps real?

• Spys.one: probablement la base de dades més completa. Pots filtrar per SOCKS5 i per país.
• Proxy-List.download: molt senzill per obtenir llistes en format text.
• Free-Proxy-List.net: ideal per a proxys ràpids, tot i que se centra més en HTTP/HTTPS.

Sample :

Also pi@R4:~/python/pkw/eines/veure_potencia_instant/5_verificar_fitxer_csv.py and pi@R4:~/python/pkw/eines/factura/1_factura.py

Input and output :

Use CSV module, specifically

Create an object that operates like a regular reader but maps the information in each row to a dict whose keys are given by the optional fieldnames parameter.

Trick : if fieldnames is omitted, the values in the first row of file f will be used as the fieldnames.

python examples - compte amb el format

els noms dels camps son a 1a linia si no es defineixen explicitament !

JSON can store lists, bools, numbers, tuples and dictionaries.
But to be saved into a file, all these structures must be reduced to strings, so they can be read or written to a file.

• json_string = json.dumps ( my_dictionary )
  Convert the python dictionary into a JSON string that can be written into a file.

• my_dictionary = json.loads ( json_string )
  Convert a JSON string into a dictionary structure.

• json.load() : read JSON data from a file and convert it into a dictionary

• json.dump() : write python serialized object as JSON formatted data into a file

Sample :

See complete doc

load() and loads() :

• to parse JSON from URL or file, use json.load()
• to parse string with JSON content, use json.loads()

A mi m'agrada sense "with" :

dump() and dumps() :

• json.dump() method is used to write Python serialized object as JSON formatted data into a file
• json.dumps() method encodes any Python object into JSON formatted string

Serialize obj to a JSON formatted string using this conversion table.

The JSON data has this format :

And we manage it like this :

educative.io : How to plot graphs using .json files in Python
Easy "line" graph and easy "bar" graph

• Vols programar? Mira python pyplot. Es potser la millor virgueria que hi ha.
• No vols programar ni automatitzar? Obre't un compte a databricks.
  Li enxufes el json i ell solet s'ho empassa tot i ho transforma a una base de dades on pots fer de tot i mes, inclus grafics clar.
  Funciona amb una cosa q es diu Jupiter.
  Si no el coneixes t'el recomano per aixo i moltes altres coses, incluida la del punt 1 a dalt.
  Es un python interactiu ficat dins del teu navegador, tot en local.

Que es ? plotting library
Matplotlib along with NumPy can be treated as the open source equivalent of MATLAB.

Tutorial, examples, nice guide, documentacio 3.9.0

matplotlib.org

Just as we use the np shorthand for NumPy and the pd shorthand for Pandas, we will use some standard shorthands for Matplotlib imports:

The plt interface is what we will use most often.

O'Reilly "Python Data Science Handbook" by Jake VanderPlas - Chapter 4. Visualization with Matplotlib {****}

I a les meves maquines :

Si en executar un python ens trobem amb

... cal instalar "matplotlib"

Minie 20240520 - version 3.5.1-2build1

Pi0 :

Matplotlib is strongly object oriented and its principal objects are the figure and the axes.

You can think of the figure as a canvas, of which you typically specify the dimensions and possibly e.g., the background color etc etc.
You use the canvas, the figure, essentially in two ways, placing other objects on it (mostly axes, but also text labels etc) and saving its contents with savefig.

You can think of an axes as a sort of Swiss Army knife, a handy object that offers a tool (e.g. .plot, .scatter, .hist etc) for everything, mostly.
You can place one, two, ... many axes inside a figure using one of many different methods.

stackoverflow

Read The Matplotlib Object Hierarchy

Matplotlib has two interfaces - API reference

• pyplot interface (function-based, implicit)
  consists of functions in the pyplot module. Figure and Axes are manipulated through these functions and are only implicitly present in the background.
  API: matplotlib.pyplot

• Axes interface (object-based, explicit)
  create a Figure and one or more Axes objects, then explicitly use methods on these objects to add data, configure limits, set labels etc.
  API: "subplots" - create Figure and Axes ; "axes" - add data, limits, labels etc. ; "Figure" - for figure-level methods

... an Axes actually translates into what we think of as an individual plot or graph (rather than the plural of “axis”)

A potentially confusing feature of Matplotlib is its dual interfaces: a convenient MATLAB-style state-based interface, and a more powerful object-oriented interface.

Matplotlib was originally written as a Python alternative for MATLAB users, and much of its syntax reflects that fact. The MATLAB-style tools are contained in the pyplot (plt) interface.

It’s important to note that this interface is stateful: it keeps track of the “current” figure and axes, which are where all plt commands are applied.
You can get a reference to these using the plt.gcf() (get current figure) and plt.gca() (get current axes) routines.

The object-oriented interface is available for these more complicated situations, and for when you want more control over your figure. Rather than depending on some notion of an “active” figure or axes, in the object-oriented interface the plotting functions are methods of explicit Figure and Axes objects.

O'Reilly

Per fer el parsing de python mes facil, lo millor es guardar les dades en format CSV

Paraules clau :

• pyplot.figure()
• pyplot.plot()
• pyplot.show()
• pyplot.savefig()
• pyplot.ylim()
• pyplot.subplot()

Permet especificar el tamany del PNG - width, height

Per defecte, treu un PNG de 640 x 480 pixels, i te per defecte DPI=100, aixi que es codifica figsize=(6.4, 4.8) per defecte

Matplotlib doesn't work with pixels directly, but rather physical sizes and DPI. If you want to display a figure with a certain pixel size, you need to know the DPI of your monitor.

For example this link will detect that for you.

Volem produir un PNG de un tamany determinat, diguem 1800 x 800 pixels :

stackoverflow

my_dpi = 96x96 {MARS}, 264x264 {Xiaomi 10}, 144x144 {tablet "Tab A8"}

Plot y versus x as lines and/or markers.

matplotlib will simply output the chart to your viewport when the .show() method is invoked

• install tkinter :
  $ sudo apt-get install python3-tk

• use TkAgg :
  import matplotlib matplotlib.use('TkAgg') import matplotlib.pyplot as plt # in this order or restart kernel ... ImportError: Cannot load backend 'TkAgg' which requires the 'tk' interactive framework, as 'headless' is currently running

• installing any of the matplotlib GUI backends like Qt5Agg, GTKAgg, Qt4Agg, etc
  $ pip install pyqt5

  And here it is, working ...

  nicolau@mars:~/sebas/python/smart_devices/termometre/dibuixar$ cat ./1_prova.py #!/usr/bin/env python3 # -*- coding: utf-8 -*- import matplotlib matplotlib.use('Qt5Agg') # pip install PyQt5 import matplotlib.pyplot as plt import numpy as np y = np.random.random(10) x = np.linspace(1, len(y), len(y)) plt.plot(x, y) plt.show(block=True) # no funciona amb "False"

stackoverflow

Use "spider", python IDE for scientists :

Save the current figure as an image or vector graphic to a file.

Amb aquesta ajuda ho treiem a fitxer !

The available output formats depend on the backend being used. Onminie, if I run the code

... we get {20250105}

It is used for setting the y-axis range (or to read it)

Es a dir, si tenim dades en el rang [38..52], per defecte el "38" sera el començament del eix "Y".
Si volem que comenci a "0", hem de posar .ylim()

Atencio : ha de estar ben aprop de .plot() - mai abans de .figure()

Add an Axes to the current figure or retrieve an existing Axes.

The default call is subplots(nrows=1, ncols=1).

nice article, as Text inside dollar signs utilizes TeX markup to put variables in italics !!!

Sempre se li ha de dir

Creant codi amb Gemini, vols fer servir

Mirem quins estils tenim :

I el resultat es :

Fem proves a MARS - obtenim PNG de 640 x 480 pixels

I amb dades reals treballem a

Compte : al PiZero hem de fer servir python3, vist que no es pot instalar matplotlib per python2

R4 : llegim texte temperatures i generem PNG :

To support all use cases, matplotlib can target different outputs, and each of these capabilities is called a backend; the "frontend" is the user facing code, i.e., the plotting code, whereas the "backend" does all the hard work behind-the-scenes to make the figure.

Matplotlib backend relies on some backend to actually render the plots. The default backend is the agg backend. This backend only renders PNGs. Docs for Matplotlib backend.

So, if you want to generate an image but not to display it, use this code :

Solucio :

• matplotlib 3.5.2 documentation

• nice how-to, as Generate images without having a window appear

• adding value labels on a matplotlib bar chart

• lines and bars {excelent}

• The 7 most popular ways to plot data in Python :
  matplotlib, seaborn, plotly, bokeh, altair, pygal, ...

• PNG tools, as resize

• simple plot samples

• recollir sys info - go
• enviar missatge a telegram - go
• manage GPIO pins - go
• web server - go
• send email, SMTP - go
• read email, IMAPLIB - go
• manage images and webcam, openCV - go
• sounds - go
• I2C and TC74 - go
• blog - go
• AWS access

Recollir informacio del sistema, escriure un fitxer HTML i enviar-lo per FTP

Resultat : PiZero , Odin , by //MARS:/home/nicolau/sebas/python/tinet/R0/enviar_ip_a_tinet.py

Enviar texte a un bot - tg.htm

What is RPi.GPIO?
It’s an easy way of controlling the Pi’s General Purpose Input Output ports in python.

If we get

We have to improve our code to execute "cleanup()" on all cases :

Read raspi.tv

From python v3 we can go one-liner :

afternerd

Per exemple, si volem mirar un codi HTML + JavaScript local, (MARS+njs+pere) obtindrem un missatge a la consola com :

Then, we start a python server and proceed :

Volem un web server lleugerament semblant a un node, es a dir que

• serveixi pagines estatiques
• faci una foto i la envii (fitxer on-request) si es prem un boto
• respongui a requeriments del client, com "a quina temperatura tens la GPU ?"

We can code :

We code :

To start, we serve this file :

And the action is performed here :

And here :

We get this interesting runtime warning :

Solution : code cleanup() as indicated here

Some URLs :

• nice class ppt

• github to display headers

• python network programming

• python 3 module of the week - base classes for implementing web servers

  http.server uses classes from socketserver to create base classes for making HTTP servers. HTTPServer can be used directly, but the BaseHTTPRequestHandler is intended to be extended to handle each protocol method (GET, POST, etc.).

• python dictionaries to/from JSON

• nice bona bibliografia : 500 lines web server

• en Albert diu de fer servir bottle - fast, simple and lightweight WSGI micro web-framework for python

1. login to Google account {pocaporpere}

2. set up a Google Cloud platform project :
   1. enter Google Cloud console
   2. "Select a project" + "New project" {top right}
   3. Projet Name := "minie python 2 Gdatasheets" + "Create"

3. enable Google Sheets API :
   1. search for "google sheets api" in top center box
   2. first entry is "Google Sheets API" + "Google Enterprise API" - click on it
   3. "Google Sheets API" page comes up - click "Enable"

4. no enable Cloud Natural Language API :
   1. search for "cloud natural language api" in top center box
   2. click "Enable"
   3. Cloud Natural Language API requires a project with a billing account

5. create API key :

   1. open top-left 3-lines and select "APIs and services", then "Credentials"

   2. click "create credentials" - here we have 3 options :
      • API key -
      • OAuth client ID -
      • Service account - get JSON file

   3. + "API key" - it is used to authenticate to the 2 API's
      With this authentication our API will only work with "public" Google Sheets
      To use "private" Google Sheets we'd need to use OAuth authentication (or Service Account ?)

      save the key for later use

   4. access using Google Service Account (JSON file)

      • go to Google Cloud Console

      • ensure the correct project is selected from the dropdown menu at the top of the page

      • navigate to Service Accounts in the navigation menu (the hamburger icon), go to IAM & Admin > Service Accounts

      • click "+ Create Service Account" nom "servei-isins"

      • create the JSON key :
        • Once you are on the Service Account details page, click the Keys tab.
        • Click the Add Key dropdown menu, and select Create new key.
        • In the dialog box that appears, select the JSON key type.
        • Click Create.

      • download the file {20251215 - isin2gss-df6e78707986.json}

6. Service Account is shared with the Sheet:

   Find the Client Email in your isin2gss-df6e78707986.json file (it looks like [account-name]@[project-id].iam.gserviceaccount.com).

   Go to your Google Spreadsheet, click the Share button, and share the spreadsheet with that specific Service Account email, giving it Editor permission.

7. enable Google API : visit here

8. to connect to Google data, we'll be using Google libraries, built in toolkits
   $ pip3 install google-api-python-client google-cloud-language

   Jo faig servir "software manager" + "python3-googleapi" v 1.7.11-4 & python3-googleapi-samples
   destinacio a minie : /usr/share/doc/python3-googleapi-samples/examples
   Homepage

9. create a Spreadsheet, and name it "miniepython2GS" :

   Here is the private spreadsheet URL and ID is "1W070QyiBSOP_bEwCIyO2wziAYoAV3F4z5QgeIkZq5E0", owned by "pocaporpere"
   Public URL

Using AI we get this code : chatGPT write GSS -> sebas@minie:~/dades/python/gugel_sheets$./4_chat_gpt.py & details (install, errors, ...)

To write to a sheet, you need the spreadsheet ID, the range of cells in A1 notation, and the data you wish to write within an appropriate request body object.
Updates require a valid ValueInputOption parameter :

• "RAW" : the input is not parsed and is inserted as a string
• "USER_ENTERED" : the input is parsed exactly as if it were entered into the Sheets UI

Single quotes are required for sheet names with spaces, special characters, or an alphanumeric combination.

The "Cells" resource represents each cell, but it doesn't have a unique ID value. Instead, row and column coordinates identify the cells.

• A1 notation
  A syntax used to define a cell or range of cells with a string that contains the sheet name plus the starting and ending cell coordinates using column letters and row numbers.
  Sheet1!A1:B2 refers to all the cells in the first two rows and columns of Sheet1.

• R1C1 notation
  A syntax used to define a cell or range of cells with a string that contains the sheet name plus the starting and ending cell coordinates using row numbers and column numbers.
  This method is less common than A1 notation, but can be useful when referencing a range of cells relative to a given cell's position.

API overview, concepts

developers.google

Simple read :

hackernoon

Basic write :

coefficient.io

If successful, the response body contains an instance of UpdateValuesResponse

To make a document, spreadsheet, or presentation available for a large audience to see, publish the file.
After you publish your file you can send a new URL to anyone or embed into your website.

Any changes you make to the original document will be updated in the published version.

1. go Sheets and login()
2. at the top left, click "File" and then "Share" and then "Publish to web"
3. copy "public" sheet URL : Fronius from R4 or xatGPT

support.google.com

El R4 escriu cada nit a aquesta pagina :

• publica
• privada de'n pocaporpere

My question was "acces to google spreadsheets from python"

1. instalem el modul :
   sebas@minie:~/dades/python/gugel_sheets$ python3 -m pip install gspread Defaulting to user installation because normal site-packages is not writeable Collecting gspread Downloading gspread-6.1.4-py3-none-any.whl (57 kB) ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ 57.6/57.6 KB 49.7 kB/s eta 0:00:00 Collecting google-auth-oauthlib>=0.4.1 Downloading google_auth_oauthlib-1.2.1-py2.py3-none-any.whl (24 kB) Collecting google-auth>=1.12.0 Downloading google_auth-2.38.0-py2.py3-none-any.whl (210 kB) ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ 210.8/210.8 KB 59.8 kB/s eta 0:00:00 Requirement already satisfied: rsa<5,>=3.1.4 in /usr/lib/python3/dist-packages (from google-auth>=1.12.0->gspread) (4.8) Requirement already satisfied: pyasn1-modules>=0.2.1 in /usr/lib/python3/dist-packages (from google-auth>=1.12.0->gspread) (0.2.1) Requirement already satisfied: cachetools<6.0,>=2.0.0 in /usr/lib/python3/dist-packages (from google-auth>=1.12.0->gspread) (5.0.0) Collecting requests-oauthlib>=0.7.0 Downloading requests_oauthlib-2.0.0-py2.py3-none-any.whl (24 kB) Requirement already satisfied: requests>=2.0.0 in /usr/lib/python3/dist-packages (from requests-oauthlib>=0.7.0->google-auth-oauthlib>=0.4.1->gspread) (2.25.1) Requirement already satisfied: oauthlib>=3.0.0 in /usr/lib/python3/dist-packages (from requests-oauthlib>=0.7.0->google-auth-oauthlib>=0.4.1->gspread) (3.2.0) Installing collected packages: requests-oauthlib, google-auth, google-auth-oauthlib, gspread Successfully installed google-auth-2.38.0 google-auth-oauthlib-1.2.1 gspread-6.1.4 requests-oauthlib-2.0.0

2. error classic :
   gspread.exceptions.SpreadsheetNotFound: <Response [200]>

   Solucio :
   you need to share the spreadsheet with the "client_email" mail id
   open the spreadsheet and then click on the "share" button (top right) and then just paste the "client_email" (email id) from JSON

   stackOverflow, gspread Docs on "Auth"

   Posem "comptexatgpt@xatgpt.iam.gserviceaccount.com" i piquem "Compartir"

3. error curios :
   gspread.exceptions.APIError: APIError: [400]: Invalid value at 'data.values[0]' (type.googleapis.com/google.protobuf.ListValue), "13:05:34 al cap de munt de tot"

   ValueRange :

   values[] array (ListValue format) The data that was read or to be written. This is an array of arrays, the outer array representing all the data and each inner array representing a major dimension. Each item in the inner array corresponds with one cell.

   Solucio - per "append_row()", el texte ha de ser un array :

   szTexte = [szHMS + " al cap de munt de tot"]

4. error similar :
   gspread.exceptions.APIError: APIError: [400]: Invalid values[1][0]: list_value { values { string_value: "txt a lloc determinat" } }

   Solucio - per "update_cell()" el texte ha de ser un string

gspread is a Python API for Google Sheets - under the hood, gspread uses Google Sheets API v4

gspread homepage (exemples), github (exemples)

Sample :

Minie escriu on-demand a aquesta pagina :

• publica
• privada de'n ignasi

I el accés es fa així :

An ISIN is a permanent, unique 12-character code used to identify a specific security, such as a stock, bond, or fund.

What is the value (e.g., stock price) for a security today?
You would typically use a Ticker Symbol for this in python.
A Ticker Symbol is specific to a single exchange.

To get the stock price (value) using python, you would typically use a library like yfinance or pandas_datareader.
Most free and popular Python libraries like yfinance only accept the Ticker Symbol (e.g., AAPL or QDVW.DE), not the ISIN directly.
Reading the current stock price (value) of an ISIN using Python requires a crucial intermediary step: Symbology Mapping.
The most robust way is by using a dedicated financial API. Two good options that support ISIN lookups are Financial Modeling Prep (FMP) and Finnhub (both often have free or developer tiers).

Financial Modeling Prep (FMP): https://site.financialmodelingprep.com/ + API Documentation: https://site.financialmodelingprep.com/developer/docs
Login (abel) ->

Finnhub: https://finnhub.io/ + API Documentation: https://finnhub.io/docs/api/introduction

• com veure si el meu Google Sheets es "public" o "private" ?

• Google spreadsheets can be shared with an email - how to know who am I sharing this spreadsheet ?

  chatGPT - to see who you're sharing a Google Spreadsheet with, follow these steps:

  1. Open the Google Spreadsheet you want to check.
  2. Click on the "Share" button in the top-right corner of the screen (it's a blue button).
  3. In the "Share with people and groups" window that appears, you'll see a list of all the people you've shared the document with. This will include:
     • Emails of people who have access to the sheet.
     • The permission level (Viewer, Commenter, Editor).
     • You may also see whether it's shared with a specific group or link (if anyone with the link can access it).
  4. If you scroll down, you can also see the link sharing settings (e.g., anyone with the link, restricted access, etc.).

  This window shows a list of everyone with access to your spreadsheet, so you can easily see who you're sharing it with.

• Sheets API v4 introduced Usage Limits, as of this writing, 300 requests per 60 seconds per project, and 60 requests per 60 seconds per user.
  When your application hits that limit, you get an APIError 429 RESOURCE_EXHAUSTED.

• API exceptions

• documentation :
  • Google Sheets API documentation
  • Google APIs Client for Python documentation
  • Google Sheets API PyDoc documentation
  • Google API python client documentation , Google API Core Library documentation
  • Google Sheets python-style access documentation , Google API Client Library for Google Sheets documentation

• Blondie Bytes video : google-api-python-client
  • starting & completed code → goo.gle -> github blondie bytes

• hackernoon

  1. create a new Service Account
     A service account represents a Google Cloud service identity, such as code running on Compute Engine VMs, App Engine apps or systems running outside Google.
     nom := "minie2GDSaccount", ID = "minie2gdsaccount"
     email := "minie2gdsaccount@analytical-rig-447516-r4.iam.gserviceaccount.com"

  2. create a new key for the service account :
     under "Actions", select "Manage Keys", then "Add Key"
     a JSON file (as "analytical-rig-447516-r4-69bcb8113d33.json") is downloaded
     it will be needed later when connecting to the Google Sheets API from a Python application

  3. share the new Google Sheets spreadsheet with your service account
     click "Share" (top right) and enter the service account email

  4. run 2_rw_gss_pere.py :
     sebas@minie:~/dades/python/gugel_sheets$ ./2_rw_gss_pere.py miniepython2GS

• read data sample, using OAuth - See getting OAuth credentials & troubleshoot authentication

  run 3_sheets_read_append-row_write-cell.py to read and write - uses gspread

• nice video - uses gspread

La Google Custom Search API (també coneguda com a JSON Custom Search API) és la solució oficial de Google per fer cerques de text o d'imatges de forma programàtica. A diferència del scraping (que és el que feies amb DuckDuckGo), aquesta API està dissenyada per a desenvolupadors, és estable i no et bloquejarà per "Ratelimit" si et mantens dins dels marges.

Com funciona?
Per utilitzar-la, no busques directament a "tot Google", sinó que crees un Motor de Cerca Personalitzat (Programmable Search Engine) i després hi connectes el teu script mitjançant una clau de seguretat.

Què necessites per començar?
Per fer-la servir al teu programa Python, necessites dues coses:

• API Key: Una clau alfanumèrica que identifica el teu projecte a Google Cloud.
• Search Engine ID (CX): Un identificador que crees a la consola de Programmable Search Engine.
  Tip: En configurar-lo, has d'activar l'opció de "Cerca d'imatges" i seleccionar l'opció de "Cercar a tota la web".

Costos
Gratis: Fins a 100 cerques al dia. Per a un script personal o de prova, sol ser suficient.
Pagament: Si necessites més, costa uns $5 per cada 1.000 cerques addicionals.

Per fer servir la Google Custom Search API, has de seguir dos processos: un a la consola de Google Cloud (per la clau) i un altre al configurador de cercadors (per l'ID del motor).

1. Ves a Google Cloud Console {usr Jhngr}
2. Si no tens cap projecte, crea'n un de nou (clica al desplegable de dalt a l'esquerra -> New Project).
   Posa-li un nom (ex: "projecte per cercar cares").
3. Al cercador superior, escriu "Custom Search API" i clica-hi.
   Clica el botó Enable (Habilitar).
4. Un cop habilitada la AOI, ves a la pestanya lateral "Credentials".
   Clica a + Create Credentials -> API Key.
5. Apareixerà una finestra amb la teva clau (comença per AIza...). Copia-la i guarda-la bé.

1. Ves a Programmable Search Engine
   Clica a Add (Afegir).
   Posa-li un nom (ex: "cercador de cares").
2. Al camp "What to search?", selecciona "Search the entire web".
3. Un cop creat el motor (engine), ves a la configuració (Customize) del cercador que acabes de fer.
   Molt important: Busca l'opció Image Search (Cerca d'imatges) i activa-la (ON).
   Busca el camp Search engine ID i copia el codi que apareix.

Requires a Google low security account

specs

Minimal example : (from here)

A more detailed code :

Mind imap tools

To access a imap server we can use this code that provides access to imaplib :

To run this python, we shall use

• "imap.py myuser@gmail.com mypwd folder_name imap.gmail.com"
• "imap.py myuser@yandex.com mypwd folder_name imap.yandex.com"

gmail account has to have less secure apps access enabled !

gmx account has to be accessed with "user@gmx.com" format as userid

Here is the working code :

• code sample
• arguments
• python 3 example , example code
• python 2

OpenCV és una llibreria de programació de codi obert dirigida principalment a la visió per computador en temps real, desenvolupada per la divisió russa d'Intel en el centre de Nijni Nóvgorod.

OpenCV homepage, wiki

Intro by Albert {2016.06.02} : OpenCV + "contours" + "webcam"

Per exemple tens el programa "python" corrent, acostes un taulell d'escacs a la webcam, i veus a la pantalla els poligons que trobi el python en temps real. T'estalvies una burrada de hores, a part que es molt divertit i avances molt depressa.

Una mica de codi python :

OpenCV profiling

Runtime options can be specified via environment variables.

• OPENCV_TRACE - enables OpenCV tracing. By default tracing is turned off. It automatically enables on active ITT backend on startup.
• OPENCV_TRACE_LOCATION - storage path to store OpenCV trace.
• OPENCV_TRACE_DEPTH_OPENCV - specify trace depth of OpenCV functions
  0 - limit is disabled
  1 - trace OpenCV entry points only, without inner details (default)
• OPENCV_TRACE_MAX_CHILDREN - limit number of traced children (useful to ignore functions with large loops)
• OPENCV_TRACE_MAX_CHILDREN_OPENCV - limit number of traced children for OpenCV calls
• OPENCV_TRACE_SYNC_OPENCL - force clFinish calls in the end of OpenCV regions (performance impact, default value is 0)

Tutorial

(20200420) I prefer webcam with Motion + browser

1. sudo apt update
2. sudo apt install python-opencv {lets use python 2 by now}
3. verify the installation :
   nicolau@nicolau-desktop:~/sebas/python/openCV$ python -c "import cv2; print(cv2.__version__)" 3.2.0

Run contours.py

//MARS//home/nicolau/sebas/python/openCV/1_captura_webcam_a_crt.py -> OK

//MARS//home/nicolau/sebas/python/openCV/2_webcam_contours.py -> OK
url

Windows Install - opencv-3.1.0.exe {20160603, win 2k8}

En executar el EXE es crea la carpeta

Compte amb els projectes : The systems PATH contains a list of folders where DLLs can be found.

So we include it in system PATH :

The easiest way to install OpenCV on Windows is to simply copy the cv2.pyd file into python's site-packages directory (e.g. C:\python27\Lib\site-packages). Here is the complete sequence.

Code

Run it

Supose we have this error : AttributeError: 'module' object has no attribute 'namedWindow'

Display CV2 contents using :

1. enter python command line : python
2. load cv2 : import cv2
3. list cv2 contents : help(cv2) -> 2.482 linies !

See //MARS/home/nicolau/sebas/python/openCV/3_veure_contingut_cv2.py

Conclusion : names are Case Sensitive and the exact name is "namedWindow"

opencv documentation !

User Interface te :

• imshow()
• namedWindow
• destroyAllWindows()
• waitKey()

"contours.py" fa servir aquestes funcions :

If we get this error :

... it means we specified a destination filename with a wrong extension.

Accepted are ".png", ".jpeg" ...

Descripció del nostre projecte :

• run Android program to capture a video containing (aprox, configurable)
  • 1 frame every 5 seconds, 12 frames/minute, 720 frames/hour, 3600 frames/5 hours (max game)
  • 1 frame every second, 60 frames/minute, 3600 frames/hour, 18000 frames/5 hours
• run batch python program to extract PGN file from video

I google "android video capture a image every 10 seconds" and find few APPs to do TimeLapse, as

• Framelapse
• Lapse It
• Tina Time-lapse : de 1 fps a 50 fps, hasta 4K.
  You simply set the photo interval and the image resolution, and you're good to go. The capture screen has just three buttons for start, pause and stop, and shows a small status bar too.
• AutoPIX - recodrs GPS location also

Look for them in Play Store

Description:

• 2 £ - free version available
• export to H264, MP4, MOV and FLV
• frame interval : 1 .. 99999
• time scale : milliseconds, seconds, minutes
• resolution : 360p .. 1080p
• output folder : /storage/C871-3D8E/Android/data/com.ui.Lapseit/files/Lapseit
• encoder : MP4, H264, MOV

Features not available in free app:

• use both phone cameras
• high definition
• enhancing effects
• resume capture
• sound tracks
• no ads
• updates

Storage use calculation :

• 7 frames at 480p using 0,34 MB

FER.CMD has "python veure.py" and says :

• tauler B/N, android a la ma, 10 jugades
• tauler marró-marró, android a la ma, 10 jugades

• background substraction
• 8-chess-caselles.py : contours extraction and detect centre of rectangle
• tauler blanc/negre : a la federació en venen; a EDAMI en venen (Francisco Giner, 42); per Internet.

Volem generar una alarma en detectar moviment en un video

video recording with motion detection, in Python

RaspberryPi home surveillance with only ~150 lines of Python code - github -> uses Flask - Flask is a micro web framework written in Python

• official sites :
  • homepage: http://opencv.org
  • docs: http://docs.opencv.org/master
  • Q&A forum: http://answers.opencv.org
  • issue tracking: https://github.com/Itseez/opencv/issues

• lots of tutorials : v 2.4, root [4.3]

• face detection / recognition :
  • openCV tutorial on recognition - large, includes theory, code samples, ...
  • face detection - cascades (fluix)
  • face detection, code at at github

• Bogotobogo

• contours

• image differences

• webcam (raspi)

• opencv tutorials : python capture video

On our Raspberry, we do :

1. enable i2c : sudo raspi-config
2. update Raspbian : sudo apt-get update
3. install tools : sudo apt-get install i2c-tools
4. get I2C bus address : i2cdetect -r -y 1
5. set register 0 to 0x5A : i2cset -y 0x20 0x00 0x5A
6. sudo apt-get install python-smbus

video 1 , video 2 , python

Some urls : control everything , relay controller , 1 channel , python code

My code at both raspberries

Blogger Data API allows client applications to view and update Blogger content - reference

Go to Blogger sag : proves python

Improve PYTHONPATH :

Now we have :

Get tls lite plus "python setup.py install" : error: Unable to find vcvarsall.bat

We have (20170127)

1. download the client library
2. download and install the ElementTree package

Verify the package is already installed with python :

Download :

Install :

Run tests :

Get it

Uncompress :

Install :

Still not seen - try again :

Now we have :

So we have permission problems :

A full working sample client, containing all the sample code shown in this document, is available in the BloggerExample.py file, under the directory gdata-python-client/samples/blogger/.

You can run the sample with the following arguments:

El resultat es :

Googl'ing gets

Que hem de fer ara ? Anem pel OAuth ! Explicació :

1. Obtain OAuth 2.0 credentials from the Google API Console {seguir "link" a "explicacio"}
   Visit the Google API Console to obtain OAuth 2.0 credentials such as a client ID and client secret that are known to both Google and your application.
2. Obtain an access token from the Google Authorization Server.
3. Send the access token to an API.
4. Refresh the access token, if necessary.

Tot va be :

Minie code : /home/sebas/dades/python/google_auth

1. visit https://console.cloud.google.com/ and log in with your Google account (benet)
2. click "Select a project" and either choose an existing project or create a new one.
   just request login
3. go to "APIs & Services" > "Library" (sota les 3 ratlles horitzontals de dalt a l'esquerra)
   search for the Google APIs your app needs (e.g., Gmail API, Drive API) and click "Enable" : Drive and Mail
4. navigate to "APIs & Services" > "OAuth consent screen"
   • App name := just_login
   • eMail := benet.papell@gmail.com
   • Audience := internal
5. go to "APIs & Services" > "Credentials" and click "Create Credentials" > "OAuth client ID"
   App type := desktop ; Name := "python_code"
6. click "Download JSON" : client_secret_530674411431-erbl6f8olnffacldaldco0hodf0m8vck.apps.googleusercontent.com.json

Here is the result :

• pyglet - simpler, elegant
• pygame - graphics
• python play sound

Where to get them :

• soundible : .wav i .mp3
• llista de locs !

Documentation :

Si no funciona, pot ser url :

Tambe pot ser

pyglet makes it easy to play and mix multiple sounds together in your game. The following example plays an MP3 file :

1. sudo apt update
2. sudo apt install pyglet : "E: Unable to locate package pyglet"
3. sudo pip install pyglet : "Successfully installed pyglet future"

As with the image loading example presented earlier, pyglet.resource.media locates the sound file in the application's directory (not the working directory). If you know the actual filesystem path (either relative or absolute), use pyglet.media.load :

xcb_connection_has_error() returned true

Short sounds, such as a gunfire shot used in a game, should be decoded in memory before they are used, so that they play more immediately and incur less of a CPU performance penalty. Specify "streaming=False" in this case:

url

This example demonstrates playing many short audio samples simultaneously, as in a game.

url with "pygame.mixer.init()" details

1. find existing launcher's icon location :
   1. right-click on desktop launcher
   2. select "Open with Text Editor"
      find something like "Icon=cinnamon-panel-launcher"
   3. use "Nemo" to locate that file -> "/usr/share/icons/hicolor/scalable/apps"
2. use it on a new launcher

Per llegir PDFs, al Minie fem servir PDFPLUMBER
Per generar ODSs, la llibreria pandas (amb el motor odfpy)

Aqui :

Escollir la "millor" IA per escriure codi Python depèn molt de les teves necessitats específiques, el teu flux de treball i el teu pressupost.
Tanmateix, hi ha diversos líders al mercat que són molt valorats per les seves capacitats:

Opció més popular i versàtil:

• GitHub Copilot

  És extremadament popular i àmpliament adoptat. S'integra perfectament amb els IDEs més utilitzats (VS Code, JetBrains) i ofereix suggeriments de codi en temps real, complecions intel·ligents i fins i tot ajuda amb la generació de proves i documentació.
  Està impulsat pel model OpenAI Codex (i ara també per GPT-4o i altres models més nous), el que el fa molt potent per generar codi rellevant i contextualitzat.

Altres opcions destacades amb característiques fortes:

• Tabnine

  Conegut per les seves suggeriments de codi sensibles al context i la seva flexibilitat. S'adapta al teu estil de codificació i pot funcionar amb models al núvol o locals, cosa que és important per a la privadesa del codi. És compatible amb molts IDEs i llenguatges.

• Amazon CodeWhisperer

  Si treballes molt amb AWS, CodeWhisperer és una opció excel·lent, ja que s'integra sense problemes amb els serveis d'AWS i està optimitzat per a desenvolupadors de Python en entorns cloud. Ofereix una versió gratuïta per a desenvolupadors individuals.

• Bito

  Aquesta eina es presenta com a molt versàtil i potent per a desenvolupadors Python. Ofereix assistència de codificació directament en IDEs populars i inclou funcions com la revisió de codi, l'explicació de codi complex i l'optimització del flux de treball.

• Cursor

  És un editor de codi basat en VS Code amb capacitats d'IA integrades. Permet interactuar amb l'IA mitjançant xat, generar codi, depurar i fins i tot fer canvis al codi mitjançant llenguatge natural.

• Aider

  Una eina de programació en parella amb IA que funciona des del terminal. És compatible amb diversos LLMs (locals i al núvol), mapeja la teva base de codi completa per a un context profund, s'integra amb Git i pot fins i tot fer correccions automàtiques basades en linters i tests.

Si la ciència de dades és el teu focus:

• Fabi.ai

  Especialment dissenyat per a analistes de dades i equips de ciència de dades. Automatitza fluxos de treball de dades, genera informes interactius i optimitza scripts de Python per a anàlisis.

Here are the top 3 AI assistants for Python coding:

• 1. Cursor - best overall with deep codebase integration and AI-first editor
• 2. GitHub Copilot - most popular, seamless IDE integration with excellent completions
• 3. Claude - strongest for complex logic and understanding nuanced requirements

Bonus: ChatGPT-4 remains excellent for explaining concepts and debugging assistance.

For pure Python work, I'd recommend starting with Cursor as it's specifically designed for AI-powered coding.

homepage

This site presents Cursor as a cutting-edge AI-powered coding tool designed to make software development more productive by integrating advanced AI models and providing deep codebase understanding.

homepage

an AI companion designed to inform, entertain, inspire, provide advice, feedback, and straightforward answers.

homepage

next-generation AI assistant, focused on being safe, accurate, and secure to help users with various tasks including writing, coding, and collaboration.

• fitxer HTML : posar "timestamp" al HTML i a la consola
  comença per posar una marca temporal a "console.log()" amb un texte com "*** comencem ***" fes servir "console.log()" en cada una de les branques en que prenguis decisions - vull un log ben ple has de marcar el titol de la pagina HTML amb una marca temporal per poder diferenciar les versions que anem generant posa-hi també el nom del programa python que la ha generat

• fitxer HTML : posar sempre les meves capçaleres
  <BASE TARGET="_top"> <meta name="robots" content="noindex,nofollow"> <meta charset="utf-8"> <LINK REL="SHORTCUT ICON" HREF="./icons/favicon.ico"> <LINK REL=STYLESHEET HREF="./sag.css" TYPE="text/css">

• programa python : fer sempre un log
  {program.log} must contain a indication of all the branches in the execution, together with the data associated with it at the end of the execution, we must have *) initial and final timestamp *) input filesnames (input data) and output filenames (output data and log)

• programa python : agafar nom del fitxer "*.py" per generar "*.log"
  i need a python program, using python3 start the code with the directive "#!/usr/bin/env python3" line, followed by the line "# -*- coding: UTF-8 -*-" next, insert a comment line containing a timestamp into the code first of all, the program has to retrive its own name (similar to "program.py") and create a filename where it shall log all actions. if program name was "program.py", the log filename shall be "program.log" start by writing a timestamp in it and remember to close the log file at program end also write there the parameters provided to the execution

• programa python : posar sempre a la capçalera
  #!/usr/bin/python3 # -*- coding: utf-8 -*-

• posa sempre aquest final per fer un modul reutilitzable :
  if __name__ == "__main__": # fem un modul reutilitzable print( "python version", platform.python_version() ) rc = my_code( sys.argv ) sys.exit()

• si ens falta un modul, mai intentis instalar-lo - avisa i acaba

sebas@minie:~/dades/ai/thermometre/dibuixar$ ./5_dades_n_fitxers_i_png.py

• no facis mai un sys.exit() des de un bloc "except" perque aixeca una altra excepcio i et faras un liu.

• wifi restart :
  os.system('sudo ip link set wlan0 down') time.sleep(1) os.system('sudo ip link set wlan0 up')

• how to set "__version__" ?

  It is a dunder

• python what goes in "__init__.py" ?

• qui actualitza el directori "__pycache__" que hi ha sota "__init__.py"

• what's the difference between a module and a package ?

• when do we use "var" to define a variable ?

• PYTHONUNBUFFERED

  Setting PYTHONUNBUFFERED=TRUE or PYTHONUNBUFFERED=1 (they are equivalent) allows for log messages to be immediately dumped to the stream instead of being buffered.

• do we need PYTHONPATH ?

  The PYTHONPATH envir var is used to locate and import other modules, as openCV

• what is NUMPY ? wiki

  NumPy is the fundamental package for scientific computing with python.

• how to verify "numpy" is working fine ?

  After installation, open python IDLE. Enter import numpy and display its version

• getting the MAC from python is quite tricky ... stackoverflow

• Documentation, language Reference, standard Library

• Intro to python

• baix i creixent

• Python Data Science Handbook { dur pero complert }

• el classic

• hard way

• altres llibreries per python - el pip es molt popular per aixo, una mena de repositori bestial de coses diverses.
  PyPI = Python Package Index (PyPI) is a repository of software for python

  Per exemple python requests (que per cert, és el millor per fer tcp/ip)

• python for Android

• python tutorials at guru99

• interesting code :
  • kbd interrupt

• pythonic argument parser

• python networking

• good site : tutorial, pop3 client, socket programming, ...

• series of articles to demonstrate how to use the modules of the python 3 standard library {***}

• lots of tutorials , lots of samples (as random number generator)

• random number generation

• use APIs to send tomorrow's weather by email - see github code, open weather map api , gmail api

• 25 python project ideas

• use pylint to improve coding style

• bytearray objects

• version 3.9
  whats new in python 3.9

• call nmap from python

• how to interact with APIs in python

• geeks : response JSON python requests - molt complert

• jQ : jq is a Linux command line utility that is easily used to extract data from JSON documents

• documenting your python code base using docstrings {#}

  Docstring conventions are described within PEP 257

• syntax checkers :
  • pylint = python code static checker
    .. follows PEP 8 style guide
  • pyflakes - passive checker of python programs

• Sorting a python dictionary: values, keys, and more

• module index - v 3.10.6

• Learn Python The Hard Way

• Structuring Your Project from "The Hitchhiker's guide to python"

• online IDE's :

  • Trinket - many libraries
    python3
    python3 3.9.6
    import requests print("requests version is (%s)." % requests.__version__) # 2.28.2

  • jDoodle online Python 3 IDE

    Available modules :

    import sys import os print(help('modules'))

• SCAPY - interactive packet manipulation library written in Python.

• argparse - parser for command-line options, arguments and sub-commands {****}

• llibres :
  • github : A Whirlwind Tour of Python {}
  • Python Data Science Handbook by Jake VanderPlas - O'Reilly
    at GitHub !
    Read the book in its entirety online at https://jakevdp.github.io/PythonDataScienceHandbook/

• Collab - allows you to write and execute Python in your browser

• python tutor - online compiler, AI tutor, and Visual Debugger for Python, Java, C, C++, and JavaScript