Repo contain my learning and experiment with python

Built In command

• Python has several build in commands to easy the day to day programming.
• Check here for available built in functions.

Boolean

• Boolean are handled in python in a bit different way. Normal convention is to use true and false for boolean. But in Python we use True and False

NoneType

• In python to represent Null we use None. Pay attention to capital N

try, except ans raise

• finally block in try and except work exactly the same as finally block in Java
• else block can be used to perform an action when there is no exception.
• raise keyword is use to throw an exception.

Commonly used python packages:

• math
• os
• random
• sys
• re
• json
• datetime

User input

• input is the function used to take user input.
• The value return by input function is string.
• You should convert the return from input call to whatever you expect as input.

age = input("enter your age:") # enter 30
type(age) # will return string
age = int(age) # Convert it to type which you expect.
type(age) # will return int

Useful string function

• capitalize - Change to upper case the first letter of the string.
• title - Change to upper case first letter of all the words in the string
• upper - Change all chars in the string to upper case
• lower - change all chars in the string to lower case
• count - return the total number of given char in the string. case sensitive.
• find - return the position of a char in the string.
• split - split the string based on the separator provided.

Tuples

• Tuple is immutable ordered list. Can contain duplicates.
• Tuple elements are access in same fashion as list.
• Tuple are created using parenthesis in place of square brackets as in list.

primes = (3,7,11)
primes[0]

: slicing use of colon for getting elements through list.

my_list = [1,2,3,45,56]
print(my_list[2:4]) # prints 3, 45
print(my_list[2:]) # prints 3, 45,56
print(my_list[:4]) # prints 1,2,3,45
print(my_list[::1]) # prints 1,2,3,45,56
print(my_list[::2]) # prints 1,3,56
print(my_list[2::2]) # prints 3,56
print(my_list[1:4:2]) # prints 2,45

classmethod vs staticmethod

• classmethod and staticmethod behave a bit similarly.
• Difference is a class method will take a class reference as argument along with other argument(if needed), where are in @staticmethod no argument are mandatory.