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VEC_$IADD_MULT16_I                Domain/OS                 VEC_$IADD_MULT16_I


NAME
     vec_$iadd_mult16_i - add one 16-bit integer vector to a scalar, multiply
     by another vector

SYNOPSIS (C)
     #include <apollo/base.h>
     #include <apollo/vec.h>

     void vec_$iadd_mult16_i(
          short int *mult_vec,
          long int &mult_inc,
          short int *add_vec,
          long int &add_inc,
          long int &length,
          short int &constant,
          short int *result_vec,
          long int &result_inc)

SYNOPSIS (Pascal)
     %include '/sys/ins/base.ins.pas';
     %include '/sys/ins/vec.ins.pas';

     procedure vec_$iadd_mult16_i(
          in mult_vec: univ vec_$integer16_vector;
          in mult_inc: integer32;
          in add_vec: univ vec_$integer16_vector;
          in add_inc: integer32;
          in length: integer32;
          in constant: integer16;
          out result_vec: univ vec_$integer16_vector;
          in result_inc: integer32);

SYNOPSIS (FORTRAN)
     %include '/sys/ins/base.ins.ftn'
     %include '/sys/ins/vec.ins.ftn'

           parameter (nvec = 10)

           integer*2 mult_vec(nvec), add_vec(nvec), result_vec(nvec), constant
           integer*4 length
           integer*4 mult_inc, add_inc, result_inc

           call vec_$iadd_mult16_i(mult_vec, mult_inc, add_vec, add_inc,
          & length, constant, result_vec, result_inc)

DESCRIPTION
     Vec_$iadd_mult16_i adds its argument vector add_vec to the scalar con-
     stant, multiplies the result by the argument vector mult_vec,  and stores
     the final result in result_vec.  It differs from vec_$add_mult_i in that
     the vectors being handled are double-precision floating point.

     This call, like all vec_$ calls ending in _i, takes a set of extra stride
     arguments, one for every vector argument.  The stride arguments determine
     which elements in the array are actually processed.  For instance, if the
     stride for a particular array is set to 3, every third element in the
     array will be processed by the routine.  The stride arguments need not be
     identical.  If all stride arguments are set to 1, this call behaves
     exactly like the version without the _i in its name.

     The calculation performed is as follows: Initialize the counter variables
     J, K, and L to the low indices of the arrays mult_vec, add_vec, and
     result_vec.  In Fortran, the low index will be 1; in C, it will be 0; in
     Pascal, it varies depending on the declaration.
     Execute the following equations length times:
     result_vec(L) = (constant + add_vec(K)) x mult_vec(J)
     J = J + mult_inc
     K = K + add_inc
     L = L + result_inc

     Note that the multiplication done by this call is point-wise.  This call
     does not perform matrix multiplication, since the product of two vectors
     is another vector of the same magnitude.

     mult_vec
          A multiplicand vector.

     mult_inc
          The stride for mult_vec.

     add_vec
          An addend vector.

     add_inc
          The stride for add_vec.

     length
          The number of elements to be summed;  normally the same as the
          number of elements in the vectors.

     constant
          The scalar constant by which add_vec is multiplied.

     result_vec
          The vector created by multiplying mult_vec by constant and adding
          the result to add_vec.

     result_inc
          The stride for result_vec.

NOTES
     When vec_$iadd_mult16_i is used to operate on matrixes in C and Pascal,
     mult_vec, add_vec, and result_vec are row vectors; in FORTRAN, they are
     column vectors.

     As in all the vec_$ calls, the result array must not overlap any of the
     input arrays; the result array may be identical to an input, but must not
     contain any subset of it.   Because of pipelining, using overlapping
     input and output arrays may cause incorrect results.

     Vec_$iadd_mult16_i, like all 16-bit integer routines, performs poorly
     when compared to the 32-bit integer routines.  Its use should be avoided
     wherever possible, especially on high-performance workstations.

SEE ALSO
     vec_$add_mult, vec_$sub_mult, vec_$mult_add, vec_$mult_sub,
     vec_$add_mult_i, vec_$dadd_mult, vec_$dadd_mult_i, vec_$iadd_mult,
     vec_$iadd_mult_i, vec_$iadd_mult16.