Cheatsheet

This cheatsheet provides a quick reference to essential Python programming concepts, including variables, data types, control structures, functions, and modules. It is designed to help you quickly recall key information while coding in Python.

2.1 Flow Control

• If Statments

  • Documentation: https://docs.python.org/3/tutorial/controlflow.html

  if Condition==True:
      Execute this block
  elif Other_Condition==True:
      Execute this block
  elif Other_Condition==True:
      Execute this block
  .
  .
  .
  elif Other_Condition==True:
      Execute this block
  else:
      Execute this block
  

• Try and Except

  • Documentation: https://docs.python.org/3/tutorial/errors.html

  try:
      Block
  except:
      Block
  finally:
      Block
  

• While Loops

  • Documentation: https://docs.python.org/3/reference/compound_stmts.html#while

  While condition==True:
      Execute This Block
  

• Range and Zip

  • Documentation: https://docs.python.org/3/tutorial/controlflow.html#the-range-function

  range(start,stop,step)
  

  • Documentation: https://docs.python.org/3/library/functions.html#zip

  zip(a,b)
  

• For Loops

  • Documentation: https://docs.python.org/3/tutorial/controlflow.html#for-statements

  for i in (iterable object):
      Execute This Block
  

  enumerate(a)
  

• Break, Continue, Pass

  • Documentation: https://docs.python.org/3/tutorial/controlflow.html#break-and-continue-statements-and-else-clauses-on-loops

  break #stops loops action
  continue #moves to the next iteration in the loop
  pass #moves onto the rest of the code block and following iterations
  

2.2 Compact Code

• One-Line If and Else

  • Documentation: https://www.codegrepper.com/code-examples/python/python+single+line+for+loop+with+if+else

  x = one_thing if condtion else another_thing
  

• Comprehensions

  • Documentation: https://docs.python.org/3/tutorial/datastructures.html#list-comprehensions

  L = [x for x in (Iterable Object) if condition == True]
  

  • Documentation: https://docs.python.org/3/tutorial/datastructures.html#sets

  S = {x for x in (Iterable Object) if condition == True}
  

  • Documentation: https://docs.python.org/3/tutorial/datastructures.html#dictionaries

  D = {key:value for key,value in Dict.items() if condition == True}
  

• Generators

  • Documentation: https://docs.python.org/3/reference/expressions.html#generator-expressions

  G = (x for x in (Iterable Object) if condition == True)
  

2.3 External Data

• User Input

  • Documentation: https://docs.python.org/3/library/functions.html#input

  input('Prompt here: ')
  

• Reading from File

  • Documentation: https://docs.python.org/3/tutorial/inputoutput.html#reading-and-writing-files

  with open("file",'r') as f:
  
      f.read() #Reads entire file
      f.read(10) #Reads 10 characters
  
      f.readline() #Reads line
      f.readline() #Reads next line
  

• Writing to File

  • Documentation: https://docs.python.org/3/tutorial/inputoutput.html#reading-and-writing-files

  with open("file",'a') as f: # or 'w' 
      f.write("appends('a')/overwrites('w')")