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VEC_$IMULT_MULT_VECTOR16          Domain/OS           VEC_$IMULT_MULT_VECTOR16


NAME
     vec_$imult_mult_vector16 - multiply three 16-bit integer vectors

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

     void vec_$imult_mult_vector16(
          short int *start_vec,
          short int *mult_vec,
          short int *mult_vec_2,
          long int &length,
          short int *result_vec)

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

     procedure vec_$imult_mult_vector16(
          in start_vec: univ vec_$integer16_vector;
          in mult_vec: univ vec_$integer16_vector;
          in mult_vec_2: univ vec_$integer16_vector;
          in length: integer32;
          out result_vec: univ vec_$integer16_vector);

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

           parameter (nvec = 10)

           integer*2 start_vec(nvec), result_vec(nvec), mult_vec(nvec), mult_vec_2(nvec)
           integer*4 length

           call vec_$imult_mult_vector16(start_vec, mult_vec, mult_vec_2, length, result_vec)

DESCRIPTION
     Vec_$imult_mult_vector16 multiplies the vectors start_vec and  mult_vec,
     multiplies the result by mult_vec_2, and stores the final result in
     result_vec.  It differs from vec_$mult_mult_vector in that the vectors
     being handled contain 16-bit integers.  The calculation performed is as
     follows:

     For each integer I such that 1 <= I <= length,
     result_vec(I) = (start_vec(I) x mult_vec(I)) x mult_vec_2(I)

     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.

     start_vec
          A multiplier vector.

     mult_vec
          A multiplier vector.

     mult_vec_2
          A multiplier vector.

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

     result_vec
          The vector created by multiplying start_vec, mult_vec, and
          mult_vec_2.

NOTES
     When vec_$imult_mult_vector16 is used to operate on matrixes in C and
     Pascal, start_vec, mult_vec, mult_vec_2, 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_$imult_mult_vector16, 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_$add_mult_vector, vec_$sub_mult_vector, vec_$mult_add_vector,
     vec_$mult_sub_vector, vec_$mult_rsub_vector, vec_$add_add_vector,
     vec_$sub_add_vector, vec_$mult_mult_vector, vec_$mult_mult_vector_i,
     vec_$dmult_mult_vector, vec_$dmult_mult_vector_i, vec_$imult_mult_vector,
     vec_$imult_mult_vector_i, vec_$imult_mult_vector16_i.