Math Vector Library 1.1 Machine Learning Extension
Programming Reference Manual C/C++
Version 1.1 DD-00004-011

4.28 vmlselud - SELU activation (first derivative)

#include <mvecml.h> 
 
void vmlselud (int n, double *restrict y, int incy, 
               double l, double a, const double *restrict x, int incx); 
void vmlseludf(int n, float *restrict y, int incy, 
               float l, float a, const float *restrict x, int incx); 
 
 
#include <mvecml64.h> 
 
void vmlselud_64(long n, double *restrict y, long incy, 
                 double l, double a, const double *restrict x, long incx); 
void vmlseludf_64(long n, float *restrict y, long incy, 
                  float l, float a, const float *restrict x, long incx);

Given an input vector x, a result vector y and constants λ and α this function computes the first derivative of the SELU activation function of the values in the x vector and stores the result in the y vector.

  .  {αex  wherex <0
y =λ  1    wherex ≥0
4.28.1 Parameters

N - INTEGER

ENTRY: Number of elements of x and y.
CONSTRAINT: n ≥1.

Y - ARRAY OF REAL

EXIT: Result vector y.
CONSTRAINT: Must contain n× incy elements.
CONSTRAINT: Must not overlap with array x.

INCY - INTEGER

ENTRY: Stride for the vector y.
CONSTRAINT: incy̸= 0.
BEHAVIOR: A negative stride will traverse the array in reverse.

L - REAL

ENTRY: Constant λ.

A - REAL

ENTRY: Constant α.

X - ARRAY OF REAL

ENTRY: Input vector x.
CONSTRAINT: Must contain n× incx elements.
CONSTRAINT: Must not overlap with array y.

INCX - INTEGER

ENTRY: Stride for the vector x.
CONSTRAINT: incx̸= 0.
BEHAVIOR: A negative stride will traverse the array in reverse.