Python

Python

Python is a very easy language comapre with c++and Java any other language. It very Easy to learn and code also have a  possiblity .

Python basic programming

Print is a statement

1. Print(“Python is easy”)

Print (“hrfcreation”)

2. String - Series of character

3. Integer -WIthout using decimal point

4. Python will run line by line ex: if you give a 1

st statement value is 10 and next

statement value is 20 it will execute line by line defenitely 2

nd

line statement 20 will

be print as a output;

Price =10

Price =20

Print(“Price”)

Question 1

Ask a person name :

name = input (“What is your name? “)

Print (‘HI’ +name )

Output

Question 2

Ask a person name and favourite colur and print a message like “the so and so

person like the so ans so colour? ”(note :after a question mark need a space )

name = input(“What is your name? ”)

favourite_colour = input(“What is your favourite colour ”)

Print(name +’likes’+favourite colour)

Output

Question 3

Ask a person biirth year and subtract with the current year and print person age as a

output

birth _year =input(“Birth year: ”)

Print(type(birth_year))

age=2019 - int(birth_year)

Print(type(age))

Print(age)

Output

Queston 4

Ask a user weight in pounds convert in to kilogram and print on the terminal

weight_lbs =input(“weight(lbs): ‘)

weight_kg=int(weight_lbs)*0.45

Print(weight_kg)

course = ‘Python for Beginers’ Print (Course [0])

:- P

course = ‘Python for Beginers’ Print (Course [-2])

o/P :- -2

Print (course [0:3])

Python

0 1 2 3

o/p :- pyt

name = ‘creation’ Print (‘name [1:-7]’)

o/p :- reation

Formatted Strings:- 1. First = ‘hrf’ Last = ‘creation’ Message = First + ‘[’ + Last + ‘] is a coder’ Print (Messsage)

o/p:-hrf[creation]is a coder

2. First = ‘hrf’ Last = ‘creation’ Message = First + ‘[’ + Last + ‘] is a coder’ msg=f’{first}[{last}]is a coder’ Print (msg)

o/p:-hrf[creation]is a coder

2. course=’Python for beginners’ Print(len(course))

o/p:-20

Upper use to print uppper case

4.course=’Python for beginners’ Print(course.upper())

o/p:-PYTHON FOR BEGINNERS

Upper use to print uppper case

Lower use to print lower case

5.course=’python’ Print(course.upper())

Print(course.lower())

Print(course)

o/p:- PYTHON//upper case

Python// lower cas

Python//first letter is upper case remainning are lower case

Atoz character- 1to26 numeric letter

P y t h o n = 0 1 2 3 4 5

P=0, y=1, t=2, h=3, o=4, n=5

6.course=’python’ Print(course find(‘y’))

Print(course find(‘h’))

o/p:-1

3

7. course=’Python is a base of Machine learning’ Print(course. Replace(‘Machine learning’,’Artificial intelligence’))

o/p:-Python is a base of Artificial intelligence

8. course=’Python’ Print(‘Python’in course)

O/p:-True//Python statements‘P’ is upper case so program run as a true statement

9. course=’Python’ Print(‘python’in course)

O/p:-True//python statement ‘p’ is lower case so program run as a false statement

10.course=’Python’ Len()

Course.upper()//output will be in a capital letters

Course.lower()//output will be in small letters

Course.title()

Course.find()//findin value (python-012345)

Course.replace()//Replacing a function.. in course

Arithmatic operation

1. print(10//3)//o/p:-3

2. Print(10/3)//o/p:-3.3333335

3. Print(10**3)//o/p:-1000

4. Print(10%3)//o/p:-1

Addition

x=5

x=x+3

Print(x)

O/p:-8

subtraction

x=5

X-=3

Print(x)

O/p:-2

Addition

x=5

x=x+3

x+=4

Print(x)

O/p:-12

Operator precedcence

X=5+5*2

Print(x)

O/p:-15//10+(5*2)=15

Exponentiation 2**3//power 2^2=4

You can use multiplication or division and addtion or subtraction

x=5+4*2**2

Operator precedence

x=(5+3)*10-3

Print(x)

O/p:-77//5+3=8*10=80-3

x=5+3*2**2

Print(x)

o/p:-17

Math function

x=2.9

Print(round(x))

O/p:-3

x=2.9

 Print(abs(-2.9)) o/p:-2.9//absolute always have a positive number.

Python basics

PYTHON

Basic

a = 1 (integer)

b = 1.1 (float)

c = 1 + 2j (complex)

d = “a” (string)

e = True (boolean)

Variables Escape sequences

\”

\’

\\

\n

x = “Python”

len(x)

x[0]

x[-1]

x[0:3]

Strings

name = f”{first} {last}”

Formatted strings

x.upper()

x.lower()

x.title()

x.strip()

x.find(“p”)

x.replace(“a”, “b”) “a” in x

String methods

round(x)

abs(x)

Numer functions

int(x)

float(x)

bool(x)

string(x)

Type conversion

Falsy values

0“”None

if x == 1:

print(“a”)

elif x == 2:

print(“b”)

else:

print(“c”)

Conditional statements Chaining comparison operators

if 18 <= age < 65:

x = “a” if n > 1 else “b”

Ternary operator

x and y (both should be true)

x or y (at least one true)

not x (inverses a boolean)

Boolean operators

For loops

for n in range(1, 10): …While loops

while n > 10: …

== (equal)

!= (not equal)

Equality operators

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Functions

def increment(number, by=1):

return number + by

increment(2, by=1)

Keyword arguments

Defining functions

Variable number of arguments

def multiply(*numbers):

for number in numbers:

print number

multiply(1, 2, 3, 4)

Variable number of keyword arguments

def save_user(**user): …

save_user(id=1, name=“Mosh”)

codewithmosh.com

Shortcuts

Start Debugging F5

Step Over F10

Step Into F11

Step Out Shift+F11

Stop Debugging Shift+F5

DEBUGGING CODING (Windows) CODING (Mac)

End of line fn+Right

Beginning of line fn+Left

End of file fn+Up

Beginning of file fn+Down

Move line Alt+Up/Down

Duplicate line Shift+Alt+Down

Comment Cmd+/

End of line End

Beginning of line Home

End of file Ctrl+End

Beginning of file Ctrl+Home

Move line Alt+Up/Down

Duplicate line Shift+Alt+Down

Comment Ctrl+/

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Lists codewithmosh.com

Creating lists

letters = ["a", "b", "c"]

matrix = [[0, 1], [1, 2]]

zeros = [0] * 5

combined = zeros + letters

numbers = list(range(20))

Accessing items

letters = ["a", "b", "c", "d"]

letters[0] # "a"

letters[-1] # "d" Slicing lists

letters[0:3] # "a", "b", "c"

letters[:3] # "a", "b", "c"

letters[0:] # "a", "b", "c", "d"

letters[:] # "a", "b", "c", "d"

letters[::2] # "a", "c"

letters[::-1] # "d", "c", "b", "a" Unpacking

first, second, *other = letters

Looping over lists

for letter in letters:

... for index, letter in enumerate(letters):

... Adding items

letters.append("e")

letters.insert(0, "-")

Removing items

letters.pop()

letters.pop(0)

letters.remove("b")

del letters[0:3]

Lists codewithmosh.com

Finding items

if "f" in letters:

letters.index("f")

Sorting lists

letters.sort()

letters.sort(reverse=True)

Custom sorting

items = [

("Product1", 10), ("Product2", 9), ("Product3", 11)

]

items.sort(key=lambda item: item[1])

Zip function

list1 = [1, 2, 3]

list2 = [10, 20, 30]

combined = list(zip(list1, list2))

# [(1, 10), (2, 20)]

Unpacking operator

list1 = [1, 2, 3]

list2 = [10, 20, 30]

combined = [*list1, “a”, *list2]

Tuples

point = 1, 2, 3

point = (1, 2, 3)

point = (1,)

point = ()

point(0:2)

x, y, z = point

if 10 in point: …

Swapping variables

x = 10

y = 11

x, y = y, x

Arrays

from array import array

numbers = array(“i”, [1, 2, 3])

Sets

first = {1, 2, 3, 4}

second = {1, 5}

first | second # {1, 2, 3, 4, 5}

first & second # {1}

first - second # {2, 3, 4}

first ^ second # {2, 3, 4, 5}

Dictionaries

point = {"x": 1, "y": 2}

point = dict(x=1, y=2)

point["z"] = 3

if "a" in point:

... point.get("a", 0) # 0

del point["x"]

for key, value in point.items():

... Comprehensions codewithmosh.com

List comprehensions

values = [x * 2 for x in range(5)]

values = [x * 2 for x in range(5) if x % 2 == 0]

Set comprehensions

values = {x * 2 for x in range(5)}

Dictionary comprehensions

values = {x: x * 2 for x in range(5)}

Generator expressions

values = {x: x * 2 for x in range(500000)}

Exceptions codewithmosh.com

Handling Exceptions

try: …

except (ValueError, ZeroDivisionError): …

else:

# no exceptions raised

finally:

# cleanup code

Raising exceptions

if x < 1:

raise ValueError(“…”)

The with statement

with open(“file.txt”) as file: …

Classes codewithmosh.com

Creating classes

class Point:

def __init__(self, x, y):

self.x = x

self.y = y

def draw(self): …

Instance vs class attributes

class Point:

default_color = “red”

def __init__(self, x, y):

self.x = x

Instance vs class methods

class Point:

def draw(self): …@classmethod

def zero(cls):

return cls(0, 0)

Magic methods

__str__() __eq__() __cmp__()

Classes codewithmosh.com

Private members

class Point:

def __init__(self, x):

self.__x = x

Properties

class Point:

def __init__(self, x):

self.__x = x

@property

def x(self):

return self.__x

@property.setter:

def x.setter(self, value):

self.__x = value

Inheritance

class FileStream(Stream):

def open(self):

super().open() …Multiple inheritance

class FlyingFish(Flyer, Swimmer): …Abstract base classes

from abc import ABC, abstractmethod

class Stream(ABC):

@abstractmethod

def read(self):

pass

Classes codewithmosh.com

Named tuples

from collections import namedtuple

Point = namedtuple(“Point”, [“x”, “y”])

point = Point(x=1, y=2)

1. String - Series of character

2. Integer -WIthout using decimal point