Playing around with math functions like squaring a number, square root, and changing a number from floating point to integer.   I add various methods to do the same tasks.

```import math

print("Here are the numbers")
numbers = []
num = 0
while num <= 20:
numbers.append(num)
num += 1
print(numbers)

print('')
print('Here are the numbers squared')
squares = []
num = 0
while num <= 20:
squares.append(num ** 2)
num += 1
print(squares)

print("\n another method takes 6 lines down to 1 lines")
print("\n method 2a: {}".format(list(x * x for x in range(20))))

print("\n method 2a even squares: {}".format(list(x * x for x in range(20) if x % 2 == 0)))
print("\n method 2b odd squares: {}".format(list(x * x for x in range(20) if x % 2 != 0)))

print("\n Here are the numbers square roots of the squared numbers")
sq_root = []
num = 0
while num <= 20:
sq_root.append(math.sqrt(squares[num]))
num += 1
print(sq_root)
print('they returned floating point from sqrt')
print('\n Here are the numbers square roots of the squared numbers converted to integer')
# Method 1 of square root
sq_root = []
num = 0
while num <= 20:
sq_root.append(int(math.sqrt(squares[num])))
num += 1
print("Method 1 of square root: {}".format(sq_root))

# Method 2 of square root single line replacing 6
print("Method 2 of square root: {}".format(list(int(math.sqrt(squares[num])) for num in range(21))))

```
```
Here are the numbers
[0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20]

Here are the numbers squared
[0, 1, 4, 9, 16, 25, 36, 49, 64, 81, 100, 121, 144, 169, 196, 225, 256, 289, 324, 361, 400]

another method takes 6 lines down to 1 lines

method 2a: [0, 1, 4, 9, 16, 25, 36, 49, 64, 81, 100, 121, 144, 169, 196, 225, 256, 289, 324, 361]

method 2a even squares: [0, 4, 16, 36, 64, 100, 144, 196, 256, 324]

method 2b odd squares: [1, 9, 25, 49, 81, 121, 169, 225, 289, 361]

Here are the numbers square roots of the squared numbers
[0.0, 1.0, 2.0, 3.0, 4.0, 5.0, 6.0, 7.0, 8.0, 9.0, 10.0, 11.0, 12.0, 13.0, 14.0, 15.0, 16.0, 17.0, 18.0, 19.0, 20.0]
they returned floating point from sqrt

Here are the numbers square roots of the squared numbers converted to integer
Method 1 of square root: [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20]
Method 2 of square root: [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20]

Process finished with exit code 0

```