The World Knows What's First - It's Everything in one

The World Knows What's First - It's Everything in one

you just no need to take care of stupid braces meanwhile your IDE will take care of your indents

Simple Hello world Execution
------------------------------------

Type Python in Console to execute the code,

example 1:

Python >>>

>> print ("Hello")
Hello

example 2:

Create a text file hello.py

print ("Hello")

Execute the command
python hello.py
Output
--------

Hello



Data Types

No need to define data types (Dynamically Typed Language ). Directly variable mapping can be done

example:
name = "Freeza"
number = 5

where name is treated as string and number is treated as integer. Its developer friendly but when it goes big it has some its own draw back as the IDE itself will not handle the issues for which Python 3 has some solution.

Type hinting

example:

def print_it (a: int ) -> int:
    return a

if __name__ == '__main__':
    value = print_it(5)
    print(value)


Integers

- without dot are integers
- with dot are floats

sample = 45
newvalue = 55.53

int(newvalue)     # 55
float(sample)      # 45.0


Strings

- word
- paragraphs
- characters

* Ascii text format in python 2 and Unicode format in python 3

example

single quotes     --  'sample 1'
double quotes    --  "sample 2"
triple double quotes -- """sample 3 """   # used for documentation

number of string functions are available for string definition.

example

- capitalise
- check if its alphabet or not
- check if its a digit
- replace characters
- csv format to value array/list (split)

Printing it on the go

text1 = "super"
text2 = "Dragonballs"

"They have something {0} called {1} in their planet".format(text1,text2)

f"They have something {text1} called {text2} in their planet"

f - format
r - raw string - doesn't do any preprocessing
u - unicode string

Slicing

s = "Dear Freeza i give you a last chance provide an apology and go away"
s[10:20]
'a i give y'



Boolean 

- True
- False 

example:

isGokuAlive = True          #int(isGokuAlive)   #str(isGokuAlive)
isGohanEating = False     #int(isGohanEating)


None 

- equally as null



Control Statements

If Statement

def is_equal(number):
    if number == 7:        # == is for checking equality   isequal
        print("there are 7 dragon balls")
    else:
        print("there are not 7 dragon balls")

number assigned other than zero has true value.

use "and" and "or" for multiple condition


List

characters = ["goku","freeza","cell"]

characters[0]

>> 'goku'

characters[-1]

>>'cell'

characters.append("gohan")
characters
>>['goku', 'freeza', 'cell', 'gohan']

"goku" in characters
>>True

len(charecters)
>>4

del charecters[2]

charecters
>>['goku', 'freeza', 'gohan']

List Slicing

charecters[1:]
['freeza', 'gohan']


charecters[1:-1]
>>['freeza']

Operations 

- push
- pop
- reverse

list comprehension 



Looping

printing elements in list using loop for printing every elements

for chars in characters:
    print("{0}".format(chars))
 
>>goku
>>freeza
>>gohan

a =0
for count in range(7):
    a+=1
    print("the number of dragon balls collected is {0}".format(a))
 
the number of dragon balls collected is 1
the number of dragon balls collected is 2
the number of dragon balls collected is 3
the number of dragon balls collected is 4
the number of dragon balls collected is 5
the number of dragon balls collected is 6
the number of dragon balls collected is 7


range(7)

range(1,10)

range(1,10,2)


Break and Continue

def check_break(pass_list):
    for available in pass_list:
        if available == "gohan":
            print( available +" is available for a fight")
        print(available + "is currently checked for availability")

if __name__ == '__main__':
    dbz_chars=["goku","pikalo","gohan","kralin","Bulma","chichi","dende","vegeta"]
    check_break(dbz_chars)

goku is currently checked for availability
pikalo is currently checked for availability
gohan is available for a fight
gohan is currently checked for availability
kralin is currently checked for availability
Bulma is currently checked for availability
chichi is currently checked for availability
dende is currently checked for availability
vegeta is currently checked for availability



def check_break(pass_list):
    for available in pass_list:
        if available == "gohan":
            print( available +" is available for a fight")
            break
        print(available + " is currently checked for availability")

if __name__ == '__main__':
    dbz_chars=["goku","pikalo","gohan","kralin","Bulma","chichi","dende","vegeta"]
    check_break(dbz_chars)


goku is currently checked for availability
pikalo is currently checked for availability
gohan is available for a fight


def check_break(pass_list):
    for available in pass_list:
        if available == "Bulma":
            continue
            print( available +" is available for a fight")
        print(available + " is currently checked for availability")

if __name__ == '__main__':
    dbz_chars=["goku","pikalo","gohan","kralin","Bulma","chichi","dende","vegeta"]
    check_break(dbz_chars)

goku is currently checked for availability
pikalo is currently checked for availability
gohan is currently checked for availability
kralin is currently checked for availability
chichi is currently checked for availability
dende is currently checked for availability
vegeta is currently checked for availability


def while_loop(x):
    while x < 7:
        print("The number is {0}".format(x))
        x+=1



if __name__ == '__main__':
    while_loop(0)

The number is 0
The number is 1
The number is 2
The number is 3
The number is 4
The number is 5
The number is 6




Dictionaries

- store key value pairs

chars = {
    "name": "Goku",
    "role": "Hero",
    "fans": "infinity"
}

chars.values()
>> dict_values(['Goku', 'infinity', 'Hero'])

chars.keys()
>>dict_keys(['name', 'fans', 'role'])


chars.get("name")
>>'Goku'


chars["name"] == "goten"
>>False

chars["name"] = "goten"

chars
>>{'name': 'goten', 'fans': 'infinity', 'role': 'Hero'}

del chars["role"]

chars
>>{'name': 'goten', 'fans': 'infinity'}


Exception

chars = {
    "name": "Goku",
    "role": "Hero",
    "fans": "infinity"
}

try:
    power_level = chars["power_level"]
except KeyError:                      #except Exception:           #except TypeError as error   -> print(error)
    print("handled exception")

-Create your own exception


Other Data Types

- long
- byte
-bytearray
- tuples , similar to list - immutable values
- set and frozenset - > no duplicates
list to set conversion will remove the duplicates as well as arranges it in ascending order


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