n = 5
for i in range(n):
print(i)
n = 5
for i in range(n):
print(i, end="")
n = 5
for i in range(n):
for j in range(n):
print(i, j)
n = 5
for i in range(n):
for j in range(n):
print(i, j, end=" | ")
print()
n = 5
for i in range(n):
for j in range(i+1):
print(i, j, end=" | ")
print()
s = "Hallo"
n = 5
for i in range(n):
print(s[i])
s = "Hallo"
for i in range(len(s)):
print(s[i])
s = "Hallo"
for i in range(len(s)):
print(s[i], end="")
s = "Hallo"
for i in range(len(s)):
for j in range(i+1):
print(s[i], end="")
print()
s = "Hallo"
for i in s:
print(i)Notes S-09/Python 6: For and while loops
Explain loop mechanics with sums and products, then distinguish the planned in-class and homework exercises.
Slide 109 — Ranges and for loops
range() accepts a start, an exclusive stop, and an optional step.
list(range(10))
list(range(6, 10))
list(range(1, 10, 2))for i in range(3):
print(i)for i in [2, 9, 7]:
x = i * 2
print(x)for i in ['apple', 'orange']:
print(i)for can iterate over ranges and directly over list elements.
Slides 110–111 — for loops
Explain loops using \(\sum_i^n\) and \(\prod_i^n\).
In-class demo ../materials/session_09/for_demo.py
Note: 3–4 and 6–7 are homework.
- Write a program that will ask the user for a message and the number of times they want that message displayed.
In-class exercise ../materials/session_09/Message.py
message = input("Enter the message: ")
n = int(input("How many times should the message be displayed: "))
for i in range(n):
print(message)- Write a program that will calculate the average (mean) of a set of numbers.
In-class exercise ../materials/session_09/Average.py
n = int(input("How many numbers do you want to enter: "))
numbers = []
for i in range(n):
numbers.append(int(input("Enter number: ")))
sum = 0
for i in range(n):
sum = sum + numbers[i]
average = sum/n
print("The average is: ", average)- Write a program that will output the numbers from 1 to 100.
Homework ../materials/session_09/Tens.py
for i in range(1,101):
if i%10==0:
print(i, " divisible by 10!")
else:
print(i)- If we list all the natural numbers below 10 that are multiples of 3 or 5, we get 3, 5, 6 and 9.
msum = 0
n = int(input("Enter the upper bound: "))
for i in range(1,n):
if(i%3==0 or i%5==0):
msum = msum + i
print(msum)- Write a program that generates a list containing the Fibonacci sequence.
In-class exercise ../materials/session_09/Fibonacci.py
n = int(input("How many numbers should be generated: "))
fib = [0,1]
for i in range(n):
fib.append(fib[-2]+fib[-1])
print(fib)- Write a program to generate n random numbers between 1 and 10.
import random
n = int(input("How many random numbers do you want to generate? "))
freqlist = [0,0,0,0,0,0,0,0,0,0]
for i in range(n):
x = random.randint(1,10)
freqlist[x-1] = freqlist[x-1] + 1
print(freqlist)- Write a program that displays a word entered by the user as a triangle of letters.
Homework ../materials/session_09/Triangle.py
word = input("Enter a word: ")
for i in range(len(word)):
for j in range(i+1):
print(word[i], end="")
print()☕ Break — 10 minutes
Slide 112 — while loops
A while loop repeats while its condition remains true. Its body must change the relevant state to avoid an infinite loop.
count = 0
while count < 4:
print("The count is:", count)
count = count + 1names = ['Ann', 'Tom', 'Peter', 'Jens', 'Sue']
while names[0] != 'Jens':
print(names[0])
names.remove(names[0])Slides 113–114 — while loops
Assign exercise 1, 5 as homework.
- Create a program that will keep track of items for a shopping list.
sl = []
item=input("Insert list item: ")
while item != "":
sl.append(item)
item=input("Insert list item: ")
for i in sl:
print(i)
sl = []
item="x"
while item != "":
item=input("Insert list item: ")
if item!="":
sl.append(item)
for i in sl:
print(i)
sl = []
item="x"
while item != "":
item=input("Insert list item: ")
if item=="":
break
sl.append(item)
for i in sl:
print(i)- Write a Python program to guess a number between 1 to 10.
In-class exercise ../materials/session_09/Guess1.py
import random
target_num = random.randint(1, 10)
guess_num = 0
while target_num != guess_num:
guess_num = int(input('Guess a number between 1 and 10 until you get it right: '))
print('Well guessed!')- Rewrite the program to have the user guess a number between 1 to 100
In-class exercise ../materials/session_09/Guess2.py
import random
target_num = random.randint(1, 100)
guess_num = 0
while target_num != guess_num:
guess_num = int(input("Guess a number: "))
if(target_num<guess_num):
print("lower")
elif(target_num>guess_num):
print("higher")
print('Well guessed!')- Expand the previously created dice game.
In-class exercise ../materials/session_09/dicegame2.py
import random
stake = int(input('How much money would you like to invest? '))
continue_ = True
while continue_:
dice1 = random.randint(1,6)
dice2 = random.randint(1,6)
if dice1 == dice2:
print("You have won!!! It's a double", dice1)
payout = stake * dice1
print("You get", payout, "Euro!")
continue_ = bool(int(input('Would you like to continue? 1=yes, 0=no: ')))
if continue_:
stake = payout
else:
print("Unfortunately they lost!!! The throw brought", dice1, "and", dice2)
continue_ = False- Write a program to create the history of a loan.
Note: Remind students that exercise 5 is the same task they completed in Excel.
Homework ../materials/session_09/Loan.py
amount = float(input("Amount of the loan: "))
repayment = float(input("Repayment: "))
irate = float(input("Interest rate (in % and annual): "))
period = 0
while amount>0.0:
period += 1
interest = amount * irate/100.0/12.0
if (amount>repayment):
amount = amount - repayment
else:
repayment = amount
amount = amount - repayment
print ("Month:", period, " Repayment:", repayment, " interest:", round(interest,2), " Remaining:", amount)Summary and announcements
TipNotes for improvement
Take notes on improvements and common questions during the session and add them to feedback.qmd afterwards.