Outputs and strings

print("Hello everyone") #outputting text
fname = "Bobby" #defining and assigning string
sname = "Jones"
print(fname + " " + sname) #joining strings

Inputting strings

name = input("Enter name: ") #string input from console
print("Hello " + name) #joining Hello with input

Integers (whole numbers)

num1 = 35 #defining and assigning integer
result = num1 * 2 #int variable times 2
num2 = int(input("Enter a number: ")) #int input from user
result = num1 - num2 #using subtraction
print("The result: " + str(result)) #converting to string

Floats (decimal places)

floaty = 2.5 #float variable assignment
num = float(input("Enter a number: ") #converting to float
answer = num / 2 #division will give a float answer
print(answer)

IF statements

num1 = 30
if num1 > 30: #if num1 bigger than 30
   print("Num 1 than 30") #notice the indent (tab key)
else: #notice no indent
   print("Num 1 less than 30")

ans = input("Capital of England: ")
if ans == "London": #if answer is london
   print("Correct!")
else:
   print("Sorry, wrong")

age = int(input("Enter age: "))
if age >= 17: #if 17 or greater
   print("Full licence")
elif age == 16: #else if 16
   print("Provisional licence")
else: #otherwise
   print("Not old enough")

While loops

x = 0
while x < 10:
   print(x)
   x += 1 #increase x by 1

#below will keep looping until the user inputs 'exit'
response = "" #empty string
while response != "exit": #loop while response NOT exit
   response = input("Continue? ") #ask user for input

For loops

for i in range(10): #looping from 0 to 9 (stopping at 10)
   print(i) #will output 0 first loop, then 1...

#code below will output times table of input number
num = int(input("Enter a number: "))
for i in range(1,13): #i will start at 1, 12 on last loop
   tot = i * num
   print(str(num)+" times "+str(i)+" = "+str(tot))

Lists (arrays)

cars = ["Honda","Ford","Audi"] #list of strings
card.append("BMW")#add element to list
cars.pop(1) #remove at index 1 (Ford)
cars.pop() #remove last element (BMW)
bikes = [] #empty list
names = [""] * 100 #list/array with 100 blank string elements
numbers = [0] * 50 #list/array with 50 integer elements
bike.append(input("Enter a bike: ")) #user inputs new item

Looping through lists

#the code below will print all elements in the list
cars = ["Honda","Ford","Audi","BMW"] #list of strings
for x in cars: #x will be each item in turn
   print(x) #print current value of x

#the code below uses an index to loop through the list
for i in range(0,len(cars)): #i 0 to end of the list
   if cars[i] == "Ford": #if current item is Ford
      print("Found at position "+i) #output index of item

Random

import random #needed to use random
rand = random.randint(0,10) #between 0 and 10
print(random.choice(cars)) #random item from a list

String manipulation

text = "Super coder"
chars = len(text) #length of string
print(chars) #output: 11
print(text[4]) #output: r
print(text[6:]) #output: coder
print(text[-5:-1]) #output: code
print(text[:-6]) #output: Super
print(text.count('e') #output: 2
if text.find("code") == -1: #find if contains "code"
   print("Not found") #if -1, not found
else:
   print("Found")
print(text.upper()) #output: SUPER CODER

Sleep (time library)

import time #needed to use time functions
time.sleep(2) #sleep for 2 seconds
#can be used in a loop to do a countdown 1 to 10
for x in range(1,11):
   time.sleep(1)
   print(x)

DIV and MOD

#int division ignores remainders e.g. below
answer = 9//2 #int division = 4 (4 twos in 9)
#MOD gives the remainder - amount left after in division remain = 9 % 5 #remain = 4 (1 five in 9, 4 remainder)

Procedures (no return value)

def power2(num): #defining sub with 1 parameter
   answer = num * num
   print(answer)

power2(9) #calling the sub with argument (9)

Functions (returns a value)

#this function a number when raised to given power
def power(num,exp): #parameter for number and exponent
   answer = num #variable to hold running result
#x = exp and decrease by 1 (-1) each loop until reaches 1
   for x in range(exp,1,-1): #decrementing loop
      answer = answer * num
   return answer #return value to main code
print(power(5,3)) #call function and print result
result = power(6,4) #call and store result in variable