Learn Python – NOTES 41 – 50

This follows the lesson plan at https://edube.org

Program 41 – If Else

if the_weather_is_good:
      go_for_a_walk()
elif tickets_are_available:
      go_to_the_theater()
elif table_is_available:
      go_for_lunch()
else:
      play_chess_at_home()

elif and else are both optional.  You can have simply an if.
If I get bit by a dog: see a doctor()

Program 42 – max() function – Also min() function

# Read three numbers.
number1 = int(input(“Enter the first number: “))
number2 = int(input(“Enter the second number: “))
number3 = int(input(“Enter the third number: “))
# Check which one of the numbers is the greatest
# and pass it to the largest_number variable.
largest_number = max(number1, number2, number3)
# Print the result.
print(“The largest number is:”, largest_number)

Program 43 – Sending a series of numbers to multiple variables.

x, y, z = 5, 10, 8

print(x > z)
# False
print((y - 5) == x) # True

Program 44 – While and For

i = 0
while i < 100: # do_something() i += 1 print(i) for i in range(100): # do_something() pass print(i) for i in range(10): print("The value of i is currently", i) for i in range(2, 8): print("The value of i is currently", i) An example: my_word = input("Enter a word: ") for letter in my_word: # Complete the body of the for loop. if letter=="a":pass elif letter=="e":pass elif letter=="i":pass elif letter=="i":pass elif letter=="u":pass else: print(letter) pass print(my_word) Program 45 – One Second Delay in print
import time
i = 0
for i in range(1,6):
print(i,”Mississippi”)
time.sleep(1)
pass
print(“Here I come.”)

Program 46 – Block Counting Program

import sys
import signal

blocks = int(input("Enter the number of blocks: "))
blocks_used=0
row_count=1
blocks = blocks - row_count

while blocks > blocks_used:
    if blocks<1:
        print("I exited here.")
        sys.exit()
    else:
#        print(row_count)
        blocks_used = blocks_used+row_count
        row_count += 1
        blocks = blocks - row_count
        print("         ( Blocks",blocks,")")
        if blocks < row_count:
            print("Pyramid is",row_count,"high.")
            Unused_blocks = blocks
            print("Blocks used: ",blocks_used+row_count)
            print("Unused blocks: ",(blocks))
            print("\n\n")
            sys.exit()
pass

Program 47 - Lothar Collatz Hypothesis

#    take any non-negative and non-zero integer number and name it c0;
#    if it's even, evaluate a new c0 as c0 ÷ 2;
#    otherwise, if it's odd, evaluate a new c0 as 3 × c0 + 1;
#    if c0 ≠ 1, skip to point 2.
import sys
    
mem_break = 0
iteration = 0
odd_even = "nothing"

c0 = int(input("Enter any value: "))

while mem_break < 100:
    mem_break += 1
    iteration += 1

    if c0 % 2 == 0:
        c0 = c0 / 2
        odd_even = "even"
    else:
        c0 = 3 * c0 + 1
        odd_even = "odd"
    print(iteration, c0, odd_even)
    if c0 == 1.0:
        print("iterations",iteration)
        print("\n\n")
        sys.exit()

Program 48 - for letter in word


import sys
    
mem_break = 0
iteration = 0


while mem_break < 100:
    mem_break += 1
    iteration += 1

    word = "Python"
    for letter in word:
        print(letter, end="*")
    
#       print("\n\n")



# sys.exit()

Program 49 - More examples


import sys
    
mem_break = 0
iteration = 0

# output:  P*y*t*h*o*n* etc

while mem_break < 100:
    mem_break += 1
    iteration += 1

    word = "Python"
    for letter in word:
        print(letter, end="*")

# output: 2 4 6 8 - no remainder

for i in range(1, 10):
    if i % 2 == 0:
        print(i)
    
# output:  OpenEDG - evaluation terminates with P

text = "OpenEDG Python Institute"
for letter in text:
    if letter == "P":
        break
    print(letter, end="")

# output:  prints pypypy right next to Open EDG without line feed

text = "pyxpyxpyx"
for letter in text:
    if letter == "x":
        continue
    print(letter, end="")

# sys.exit()

Program 50 - More reference - While Else


import sys
    
mem_break = 0
iteration = 0

# output:  P*y*t*h*o*n* etc
n = 0

while mem_break < 20:
    mem_break += 1
    iteration += 1


    while n != 3:
        print(n)
        n += 1
    else:
        print(n, "else")

    print()

    for i in range(0, 3):
        print(i)
    else:
        print(i, "else")


for i in range(3):
    print(i, end=" ")  # Outputs: 0 1 2

for i in range(6, 1, -2):
    print(i, end=" ")  # Outputs: 6, 4, 2