Raises the elements in input a to the powers given in input b element by element. The output is a complex value if and only if the input is a complex value. For instance, square root of -1 will be complex i only if the input type is complex. Otherwise, a negative number raised to a non-integer power will be NAN. However, -1 raised to the power of infinity or -infinity returns 1. Likewise, 1 raised to any power, including +/-infinity and NAN, returns 1.
a: a numeric (scalar) value, matrix or tensor.
b: Exponent of the power operation. For instance, 0.5 means square root.
output: input raised to power. The type of elements in the output matrix or tensor is always double regardless of the input type.