VEC_$DSUB_CONSTANT_I Domain/OS VEC_$DSUB_CONSTANT_I
NAME
vec_$dsub_constant_i - subtract a double-precision vector from a scalar
SYNOPSIS (C)
#include <apollo/base.h>
#include <apollo/vec.h>
void vec_$dsub_constant_i(
double *start_vec,
long int &start_inc,
long int &length,
double &constant,
double *result_vec,
long int &result_inc)
SYNOPSIS (Pascal)
%include '/sys/ins/base.ins.pas';
%include '/sys/ins/vec.ins.pas';
procedure vec_$dsub_constant_i(
in start_vec: univ vec_$double_vector;
in start_inc: integer32;
in length: integer32;
in constant: double;
out result_vec: univ vec_$double_vector;
in result_inc: integer32);
SYNOPSIS (FORTRAN)
%include '/sys/ins/base.ins.ftn'
%include '/sys/ins/vec.ins.ftn'
parameter (nvec = 10)
real*4 start_vec(nvec), result_vec(nvec), constant
integer*4 length
integer*4 start_inc, result_inc
call vec_$dsub_constant_i(start_vec, start_inc, length,
& constant, result_vec, result_inc)
DESCRIPTION
Vec_$dsub_constant_i subtracts the vector start_vec from the scalar con-
stant and stores the final result in result_vec.
This call, like all vec_$ 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 vari-
ables J and K to the low indices of the arrays start_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(K) = constant - start_vec(J)
J = J + start_inc
K = K + result_inc
start_vec
The vector to be subtracted from constant.
start_inc
The stride for start_vec.
length
The number of elements to be operated on; normally the same as the
number of elements in the vectors.
constant
The scalar from which start_vec is subtracted.
result_vec
The vector created by subtracting start_vec from constant.
result_inc
The stride for result_vec.
NOTES
When vec_$dsub_constant_i is used to operate on matrixes in C and Pascal,
start_vec and result_vec are row vectors; in FORTRAN, they are column
vectors.
As in all the vec_$ 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.
SEE ALSO
vec_$add_constant, vec_$mult_constant, vec_$sub_constant_i,
vec_$sub_constant, vec_$dsub_constant, vec_$isub_constant,
vec_$isub_constant_i, vec_$isub_constant16, vec_$isub_constant16_i.