Some notes to learn python (Basics: Part one)
#To write “Hello, World!” in the command line:
#type “python” then : print (“Hello World”);
#to exist type :exit()
# Docsting is an extendes documentation capability=> it’a a comment
# using a triple quotes at the beginning and end of the doctsting.
# A variable is created when u assign a value to it.
#No need to be declared with any particular type it can change type after have been set.
#name varaible can belongs to ([A-z][0–9][_]) and must start with letter or underscores. “Variable name are case-sentive”.
# print statment can be used to output variables
# “+” can be used to combine text and var or even 2 var.
# Combine a number with string lead to an error.
# 3 numeric type
#int : 1 , 35655555554887711 , -3255522
#float 2.8 , -32.59 , 3.0 , 37e3 , 24E4 , -87.7e100
#complex 2j , 3+5j
# type() fucntion to verify the type of the object
# if we want to specify the type of the varibale we use casting.
# because is an OO language so it use classes to define types. the cast is done by using constructor functions.
# int() to cast to integer
# float () to cast to float
# str() to cast to string
# Surounded by either single qotation marks, or double quotation marks
# it can be output to screen using print funcion
#String is an array of bytes representing unicode characters. However, Python does not have a character data type, a single character is simply a string with a length of 1. Square brackets can be used to access elements of the string.
#strip() methode to remove any whitespace from the beginig or the end.
#len() to return the length of the string
#lower() return the string in lower case
#upper() returns the string in upper case
#replace() replaces a string with another string
#split() splits the string to substr. Should define the instances of the separator:
Command-line String Input
# to Ask user for input we can use input() methode
check link it’s more useful : operators