Basic Python jupyter notebook

 

Variable

a = 10
c = 10.2
b = False
d = 'A'
e = "Apple"

print(a)
print(b)
print(c)
print(d)
print(e)

10
False
10.2
A
Apple

Operator & Precedence

result = 10 + 20
print(result)

result = 1 + 1 * 10 + 30
print(result)

result = 1 + 2 * 10 + 30
print(result)

result = (1 + 1) * (10 + 30)
print(result)

30
41
51
80

Function

def delivery_check(pincode):
    print("delivery to ",pincode)

delivery_check("600100")

delivery to  600100

Main function

def start():
    print("Hello from main function")
    
if __name__ == "__main__":
    start()

Hello from main function

Class, Object and Method

class Order:
    def __init__(self,id,pincode):
        self.id = id
        self.pincode = pincode
    def display(self):
        text = "Order : {id}, to : {pincode}"
        print(text.format(id = self.id,pincode=self.pincode))

order = Order(101,600100)
order.display()

Order : 101, to : 600100

Inheritence

class NonVegOrder(Order):
    def __init__(self,id,pincode):
        super().__init__(id,pincode)
        
order = NonVegOrder(101,600100)
order.display()

Order : 101, to : 600100

String & Array

name = "Test"
char_name = ['p','y','t','h','o','n']
name = ""
new_name = name.join(char_name)
print(new_name)
print(name)

python
Test

List & Loop

char_name = ['p','y','t','h','o','n']
name = ""
for c in char_name:
    name = name + c
    
print(name)    

['p', 'y', 't', 'h', 'o', 'n', '.']

List

names = list(("Ranjith","Raj"))
print("Names length : ",len(names))
names.append('D')
print(names)

Names length :  2
['Ranjith', 'Raj', 'D']

Array

import array as a

digits = a.array("i",[1,2,3])
for d in digits:
    print(d)

1
2
3

if & else

check = False
if check :
    print("Its true")
else:
    print("Its false")

Its false

Dictionary

map = {
    "java": 100,
    "rust" : 200,
    "python": 300
}
print(map["java"])

100

Read input

number = int(input("Enter input"))
if number < 10:
    print("Number less than 10")
else:
    print("Number greater than or equal to 10")

Enter input23
Number greater than or equal to 10

Import

import time


print(time.ctime(time.time()))
    

Sat Aug 15 20:24:50 2020

Threading

import threading

def printme(name):
    print(name)

thread = threading.Thread(printme("first"))
thread.start()

first

Multi threading

import threading
import time


class MyThread(threading.Thread):
    def __init__(self, name,count,sleep_time):
        threading.Thread.__init__(self)
        self.name = name
        self.count = count
        self.sleep_time = sleep_time
        
    def run(self):
        for i in range(0, self.count):
            print(self.name,i)
            time.sleep(self.sleep_time)


thread1 = MyThread("Fast",5,0.5)
thread2 = MyThread("Slow",5,1)
thread1.start()
thread2.start()
print("Main thread done")

Fast 0
Slow 0
Main thread done
Fast 1
Slow 1
Fast 2
Fast 3
Slow 2
Fast 4
Slow 3
Slow 4

Thread join

import threading
import time


class MyThread(threading.Thread):
    def __init__(self, name,count,sleep_time):
        threading.Thread.__init__(self)
        self.name = name
        self.count = count
        self.sleep_time = sleep_time
        
    def run(self):
        for i in range(0, self.count):
            print(self.name,i)
            time.sleep(self.sleep_time)


thread1 = MyThread("Fast",5,0.5)
thread2 = MyThread("Slow",5,1)
thread1.start()
thread2.start()
thread1.join() # Current Main thread joined to thread1 to complete
thread2.join() # Current Main thread joined to thread2 to complete 
print("Main thread done")

FastSlow 0
 0
Fast 1
SlowFast 1
 2
Fast 3
Slow 2
Fast 4
Main thread done
Slow 3
Slow 4

Logging

import logging

logger = logging.getLogger('MyApplication')
logger.info('This is to showcase info level logging in python')
level = "Warning"
logger.info('This is to showcase %s level logging in python',level)

21:08:57: This is to showcase info level logging in python
21:08:57: This is to showcase Warning level logging in python

JSON

import json

order = '{"id" : 10,"user" : "ranjith"}'

order_json = json.loads(order) # Convert string to json
print(order_json['id'])
print(json.dumps(order_json)) # Convert json to string

10
{"id": 10, "user": "ranjith"}