nd4j-backends/nd4j-api-parent/nd4j-api/src/main/java/org/nd4j/linalg/util/ComplexUtil.java
public static IComplexFloat exp(IComplexFloat d) {
        return Nd4j.createFloat((float) FastMath.exp(d.realComponent()) * (float) FastMath.cos(d.imaginaryComponent()),
                        (float) FastMath.exp(d.realComponent()) * (float) FastMath.sin(d.imaginaryComponent()));
    }
public static IComplexFloat exp(IComplexFloat d) {
        return Nd4j.createFloat((float) FastMath.exp(d.realComponent()) * (float) FastMath.cos(d.imaginaryComponent()),
                        (float) FastMath.exp(d.realComponent()) * (float) FastMath.sin(d.imaginaryComponent()));
    }
Returns the exp of a complex number:
Let r be the realComponent component and i be the imaginary
Let ret be the complex number returned
ret -> exp(r) * cos(i), exp(r) * sin(i)
where the first number is the realComponent component
and the second number is the imaginary component

@param d the number to getFromOrigin the exp of
@return the exponential of this complex number