Contents
idamax - return the index of the element with largest abso-
lute value.
INTEGER FUNCTION IDAMAX(N, X, INCX)
INTEGER N, INCX
DOUBLE PRECISION X(*)
INTEGER*8 FUNCTION IDAMAX_64(N, X, INCX)
INTEGER*8 N, INCX
DOUBLE PRECISION X(*)
F95 INTERFACE
INTEGER FUNCTION IAMAX([N], X, [INCX])
INTEGER :: N, INCX
REAL(8), DIMENSION(:) :: X
INTEGER(8) FUNCTION IAMAX_64([N], X, [INCX])
INTEGER(8) :: N, INCX
REAL(8), DIMENSION(:) :: X
C INTERFACE
#include <sunperf.h>
int idamax(int n, double *x, int incx);
long idamax_64(long n, double *x, long incx);
idamax return the index of the element in x with largest
absolute value where x is an n-vector.
N (input)
On entry, N specifies the number of elements in
the vector. N must be at least one for the sub-
routine to have any visible effect. Unchanged on
exit.
X (input)
( 1 + ( n - 1 )*abs( INCX ) ). On entry, the
incremented array X must contain the vector x.
Unchanged on exit.
INCX (input)
On entry, INCX specifies the increment for the
elements of X. INCX must be positive. Unchanged
on exit.
If the vector contains all NaNs, the function returns 1. If
the vector contains valid floating point numbers and one or
more NaNs, the routine returns the index of the lement con-
taining the largest absolute value.