Python

Python

1. Basic information

   • Compilation vs. interpretation
     • Python is an interpreted language.
   • debugger
     • a computer program that assists in the detection and correction of errors in other computer programs.
   • console :text-only computer interface,
   • case sensitive.
   • Python is a cross-platform programming language, which means that it can run on multiple platforms like Windows, macOs
   • , Cython and Jython : interpreter
   • Cython:Python programming language, designed to give C-like performance with code that is mostly written in Python.
   • dynamically-typed language, which means you don't need to declare variables in it
   • CPython

2. Data types

   • A literal is data whose values are determined by the literal itself. Ex : 12 The simplest expression is a literal itself.
   • Integers int
     • The use of underscores in numeric literals is ok EX: 111_111
     • octal value. = 0o456 = zero + o , Base 8
     • hexadecimal numbers. = 0x345 = zero + x , Base : 16
   • floating-point : float
     • scientific notation. = 5E6
   • Strings
     • An empty string still remains a string
   • Boolean values
     • True1 - False 0 / case-sensitivity.
   • None
   • type(x) = return the data type

3. variables

4. operators \modulo

   • https://edube.org/learn/pe-1/operators-data-manipulation-tools-29
   • +, -, *, /, //, %, **
     • 2 ** 3 = 2 to the power 3.
       • when both ** arguments are integers, the result is an integer, too;when at least one ** argument is a float, the result is a float, too int & int = int  int & float = float  float & int = float  float & float = float print(2 ** 2 ** 3) = 2 ** 3 → 8; 2 ** 8 → 256 right-sided binding.
     • / division
       • int & int = int  int & float = float  float & int = float  float & float = float
     • floor division\integer division : 6 // 4 = 1
       • rounded to the nearest integer value that is less than the real (not rounded) result. int & int = int  int & float = float float & int = float  float & float = int 
     • remainder (modulo): %
       • the value left over after dividing one value by another to produce an integer quotient.
   • compound assignment operators (shortcut operators)x *= 2 \ variable op= expression \ var = var / 2 ⇒ var /= 2

5. function

   • https://docs.python.org/3/library/functions.html
   • print()
     • multiple arguments : print( variable , "string" , "nhhnjj")
   • float(x)
   • str()
   • Rounf
   • input()
     • the result of the input() function is a string.

6. escape character,

   • \n newline
   • \\ display \
   • \" display "

7. keyword arguments - parameters

   • end = " " : print("My name is", "Python.", end=" ")
     • determines the characters the print() function sends to the output once it reaches the end of its positional arguments. EXprint("My name is", "Python.", end="salma ") print("Monty Python.") out My name is Python.salma Monty Python.
   • sep= "" : print("My", "name", "is", "Monty", "Python.", sep="-")
     • My-name-is-Monty-Python.

8. Extra note

   • "string" * 2 = will produce "stringstring"

9. Expression

10. Comment

    • to add : #
    • To uncomment multiple lines : Ctrl + \

11. Conditional Execution

    • if true_or_not: do_this_if_true
      • the if keyword;one or more white spaces;an expression (a question or an answer) whose value will be interpreted solely in terms of True (when its value is non-zero) and False (when it is equal to zero);a colon followed by a newline;an indented instruction or set of instructions (at least one instruction is absolutely required); the indentation may be achieved in two ways - by inserting a particular number of spaces (the recommendation is to use four spaces of indentation), or by using the tab character; note: if there is more than one instruction in the indented part, the indentation should be the same in all lines; even though it may look the same if you use tabs mixed with spaces, it's important to make all indentations exactly the same - Python 3 does not allow mixing spaces and tabs for indentation.

12. Loops

13. relational operators

    • Comparison == \ low priority
    • Inequality !=
    • > >= < <+ priority is greater than that shown by == and !=

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