##### Synopsis
```float powf(float,
float);```
##### Description

powf computes x raised to the power y.

If x < 0 and y ≤ 0, errno. is set to EDOM and powf returns −HUGE_VALF. If x ≤ 0 and y is not an integer value, errno is set to EDOM and pow returns −HUGE_VALF.

If y = 0, powf returns 1.
If y = 1, powf returns x.
If y = NaN, powf returns NaN.
If x = NaN and y is anything other than 0, powf returns NaN.
If x < −1 or 1 < x, and y = +∞, powf returns +∞.
If x < −1 or 1 < x, and y = −∞, powf returns 0.
If −1 < x < 1 and y = +∞, powf returns +0.
If −1 < x < 1 and y = −∞, powf returns +∞.
If x = +1 or x = −1 and y = +∞ or y = −∞, powf returns NaN.
If x = +0 and y > 0 and y ≠ NaN, powf returns +0.
If x = −0 and y > 0 and y ≠ NaN or y not an odd integer, powf returns +0.
If x = +0 and y and y ≠ NaN, powf returns +∞.
If x = −0 and y > 0 and y ≠ NaN or y not an odd integer, powf returns +∞.
If x = −0 and y is an odd integer, powf returns −0.
If x = +∞ and y > 0 and y ≠ NaN, powf returns +∞.
If x = +∞ and y < 0 and y ≠ NaN, powf returns +0.
If x = −∞, powf returns powf(−0, y)
If x < 0 and x ≠ ∞ and y is a non-integer, powf returns NaN.