PythonBasics

To run

git clone https://github.com/AlexDesBen/PythonBasics.git
cd PythonBasics/script/HelloWorld/
python Main.py
cd ../ExampleNumpy/
python Main.py

To know

Importing libraries

import library
import library as nickname
from library import module
from library import module as nickname

With a library you can use all the modules and sub modules like this :

library.module()
library.module.submodules()

Never do :

from library import *

It imports the library directly in the script without namespace and might crush already imported modules.

Printing to screen

print("string of text")

if, for & while

The syntax is as follow :

• if :

   if foo == bar:
     print("yes")
   elif foo == "woody":
     print("Gone!!")
   else:
     print("Caribou!")

• for :

   L = ["spam", "spamety", "spamspam"]
   for element in L:
     print(element)

• while :

   i = 0
   while i < 3:
     print(L[i])
     i += 1

Objects

With Python, everything is an object. See documentation for further information.

Examples :

x = "string of text"
x.isalpha()            # Will return True because all the chars in x are alpha
x.isalnum()            # Will return True because all the chars in x are alphanumerical
x.isdigit()            # Will return False because the chars in x are not all numbers
print(x.upper())       # Will print string will all chars capitalized
print(x.capitalize()) # Will print string but with first char capitalized

def

In python you can define functions like this :

def SomeFunction(argument1, argument2):
  temp = argument1 + argument2  # Add both arguments
  output = temp**2              # Square variable temp
  return output                 # Return the value of the variable output

... and used them this way in a script :

x = SomeFunction(2, 3)
print(x) # Would return (2+3)**2 = 25

Class

In python you can define your own classes, and inherit from other classes :

class MyClass(ParentClass):  # Leave empty of there is no need for a Parent class
  def __init__(self, arg1, arg2, arg3, ...):
	ParentClass.__init__(self, arg1, arg2, ...)
	self.stuff = arg1
	self.otherStuff = arg2
	self.lastBitOfStuff = arg3

  def NewMethod(self, SomeArgument):
	self.stuff = SomeArgument

In the code :

################################################################################
##### Definite useful classes ##################################################
################################################################################
class Human():
  def __init__(self, Name, Age):
	self.Name = Name
	self.Age = Age

  def setName(self,NewName):
  	# Will change my name and make sure it's capitalized
	self.Name = NewName.capitalize()

################################################################################
##### Main script ##############################################################
################################################################################
if __name__ == "__main__":
  Me = Human("Alex", 33)
  print(Me.Age)                        # Will print my age, 33
  print(Me.Name)                       # Will print my name, Alex
  Me.setName("charles")                # Will change my name to Charles
  print(Me.Name)                       # Will print my name, Charles