Ways to compute the squares of the integers between 1 and 5

On this page click on the code samples to execute them.

1. The for loop combined with the range function is the most direct approach:

   Animate squares-1
   
   

   for i in range(1, 6):
    print(i**2)

2. It is also possible to combine a while loop with the incrementation of a variable at each iteration of the loop:

   Animate squares-2
   
   

   i = 1
while i <= 5:
    print(i**2)
    i = i + 1

3. The order of the values can be reversed by using a decrementation:

   Animate squares-3
   
   

   i = 5
while i > 0:
    print(i**2)
    i = i - 1

4. Summing the odd integers with a while loop reaches the same result without using the ** operator:

   Single-step squares-4
   
   

   i = 1
n = 1
while i < 10:
    print(n)
    i = i + 2
    n = n + i

5. A recursive function is another approach which has a certain similarity with the while loop:

   Single-step console
   
   

   >>> def f(i, n):
...     if i < 10:
...         print(n)
...         f(i + 2, n + i + 2)
... 
>>> f(1, 1)
    1
    4

6. Using the functional programming approach a solution in one line is possible:

   Execute squares-6
   
   

   list(map(lambda i: print((i+1)**2), range(5)))

7. The previous approaches have the merit of a certain generality which the following solution lacks:

   Bundle squares-7
   
   

   print(1)
print(4)
print(9)
print(16)
print(25)

8. The results can be put in a CSV file and then displayed in a spreadsheet and a bar chart:

   Execute squares-8
   
   

   # Create a CSV file containing the squares.

with open('squares.csv', 'w') as f:
    f.write('N,N**2\n')
    for i in range(1, 6):
        f.write(str(i) + ',' + str(i**2) + '\n')

# Display it as a spreadsheet.

show_file('squares.csv')

# Display it as a bar chart.

chart(read_file('squares.csv'), mark='bar', x_type='ordinal')

9. The results could also be drawn using the turtle metaphor (here executing as a standalone web app):

   squares-9
   
   

   # This program uses the turtle to draw the
# numbers using 7 segments.

from turtle import hop, lt, rt, fd, pensize

dist = 20  # length of each segment

segments = {  # the 7 segments of each symbol
    ' ':0,
    '0':63, '1':12,  '2':118, '3':94,  '4':77,
    '5':91, '6':123, '7':14,  '8':127, '9':95
}

def print_char(c):  # draw a symbol
    lt(90)
    hop(); fd(dist)
    bits = segments[c]  # each bit = 1 segment
    for i in range(7):
        if (bits & 1) == 0: hop()
        fd(dist)
        bits >>= 1
        if i != 2: rt(90)
    hop(); fd(dist)
    lt(90)
    hop(); fd(dist/2)

def print(n):  # print a number
    for c in str(n):
        print_char(c)
    print_char(' ')

hop(); fd(-175); pensize(5)

for i in range(1, 6):  # compute the squares
    print(i**2)