List selected vector elements

SLSTxx/DLSTxx/ILSTxx/CLSTxx/ZLSTxx

Name SLSTxx/DLSTxx/ILSTxx/CLSTxx/ZLSTxx

List selected vector elements

Purpose Given a real, integer, or complex vector x of length n, these subprograms search sequentially through the vector and fill an array with a list of the indices i for which the elements xi satisfy a specified relationship to a given scalar a.

The last two characters of the subprogram name specify the relationship of interest between the elements of the vector and the scalar. For real and integer subprograms, these characters, represented by “xx” in the prototype Fortran statements, and the corresponding list contents can be:

xx

List contents

EQ

{i : xi = a}

GE

{i : xi ≥ a}

GT

{i : xi > a}

LE

{i : xi ≤ a}

LT

{i : xi < a}

NE

{i : xi ≠ a}

 

 

For complex subprograms, these characters and corresponding list contents are:

xx

List contents

EQ

{i : xi = a}

NE

{i : xi ≠ a}

 

 

The vector can be stored in a one-dimensional array or in either a row or a column of a two-dimensional array.

Usage

VECLIB:

 

 

INTEGER*4

n, incx, nindx, indx(n)

 

REAL*4

a, x(lenx)

 

CALL SLSTxx(n, x, incx, a, nindx, indx)

 

INTEGER*4

n, incx, nindx, indx(n)

 

REAL*8

a, x(lenx)

 

CALL DLSTxx(n, x, incx, a, nindx, indx)

 

INTEGER*4

n, incx, nindx, indx(n), a, x(lenx)

CALL ILSTxx(n, x, incx, a, nindx, indx)

Chapter 2 Basic Vector Operations 99