vec_zero_i() — Apollo

VEC_$ZERO_I                       Domain/OS                        VEC_$ZERO_I


NAME
     vec_$zero_i - zero a vector in a single-precision matrix

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

     void vec_$zero_i(
          float *vector,
          long int &inc,
          long int &length)

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

     procedure vec_$zero_i(
          var vector: univ vec_$real_vector;
          in inc: integer32;
          in length: integer32);

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

           parameter (nvec = 10)

           real vector(nvec)
           integer*4 length, inc

           call vec_$zero_i(vector, inc, length)

DESCRIPTION
     Vec_$zero_i zeros the length elements of the single-precision array vec-
     tor selected by inc.

     Through appropriate choice of inc, a program can use vec_$zero_i to zero
     a vector within a matrix.  To search the Mth vector in a matrix, choose
     inc equal to the number of vectors in the matrix, and place the Mth ele-
     ment of the matrix array at the beginning of vector.

     In C, the resulting operation is

          j = 0;
          for (i = 0; i < length; ++i) {
               vector[i] = 0.0;
               j += inc;
          }

     In Pascal, the resulting operation is

          j := 1;
          for i := 1 to length do
               begin
               vector[i] := 0.0;
               j := j + inc;
               end

     In FORTRAN, the resulting operation is

           j = 1
           do 10 i = 1, length
               vec(j) = 0.0
               j = j + inc
       10  continue

     vector
          The vector to be zeroed.

     inc  An increment for the index of vector that chooses the elements to be
          zeroed.

     length
          The number of elements in vector to zero.

NOTES
     In C and Pascal, vec_$zero_i zeros column vectors; whereas in FORTRAN, it
     zeros row vectors.

SEE ALSO
     vec_$dzero_i, vec_$izero16_i, vec_$izero_i, vec_$zero.
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