Normally, we calculate power of a number as:
25 = 2 x 2 x 2 x 2 x 2 = 32
53 = 5 x 5 x 5 = 125
92 = 9 x 9 = 81
As we see, Python has a built-in function to calculate the power of a given number. Let's see:
Definition of pow()
pow() is a built-in function in Python that is used to compute the power of a given number. If the number is x and the power is y then pow() returns x to the power y that is xy or x**y. The function pow() takes three parameters x which is the base number, y which is the exponent and the third parameter z which is optional is used to calculate the modulus that is (x**y)% zpow(x,y) is equivalent to x**y that is xypow(x,y,z) is equivalent to (x**y)%z
Syntax of pow()
pow(x,y,z)
Parameter | Description | Required/Optional |
|---|---|---|
x | The base number | Required |
y | The exponent, that is the value of the power | Required |
z | The value to calculate the modulus | Optional |
Let's get to the examples of pow()
Examples of pow()
p = pow(5, 3) # 5<sup>3</sup>
print(p)
q = pow(2, 5) # 2<sup>5</sup>
print(q)
r = pow(3, 4) # 3<sup>4</sup>
print(r)
125
32
81
Let's see whether it works with negative numbers as well:
p = pow(-2, 3)
print(p)
q = pow(2, -2)
print(q)
r = pow(-3, -2)
print(r)
-8
0.25
0.1111111111111111
Let's see some examples with the third parameter of pow():
p = pow(2, 3, 3) # (2**3)%3
print(p)
q = pow(5, 2, 4) # (5**2)%4
print(q)
r = pow(4, 4, 7) # (4**4)%7
print(r)
2
1
4
pow() also works with floating numbers and other numeric formats too. Let's see:# binary
print(pow(0b1010, 2)) # 0b1010 = 100
# float
print(pow(2.2, 3))
# hexadecimal
print(pow(0x15, 2)) # 0x15 = 21
100
10.648000000000003
441
