HP MLIB User's Guide Vol. 1 7th Ed.

Chapter 2 Basic Vector Operations 41

Index of maximum of magnitudes ISAMAX/IDAMAX/IIAMAX/ICAMAX/IZAMAX

INTEGER*4 i, ICAMAX, n, incx

COMPLEX*8 x(lenx)

i = ICAMAX(n, x, incx)

INTEGER*4 i, IZAMAX, n, incx

COMPLEX*16 x(lenx)

i = IZAMAX(n, x, incx)

VECLIB8:

INTEGER*8 i, ISAMAX, n, incx

REAL*4 x(lenx)

i = ISAMAX(n, x, incx)

INTEGER*8 i, IDAMAX, n, incx

REAL*8 x(lenx)

i = IDAMAX(n, x, incx)

INTEGER*8 i, IIAMAX, n, incx, x(lenx)

i = IIAMAX(n, x, incx)

INTEGER*8 i, ICAMAX, n, incx

COMPLEX*8 x(lenx)

i = ICAMAX(n, x, incx)

INTEGER*8 i, IZAMAX, n, incx

COMPLEX*16 x(lenx)

i = IZAMAX(n, x, incx)

Input n Number of elements of vector x to be used. If n ≤ 0, the

subprograms do not reference x.

x Array of length lenx = (n−1)×|incx|+1 containing the

n-vector x.

incx Increment for the array x. x is stored forward in array x

with increment |incx|; that is, x

is stored in

x((i−1) ×|incx|+1).

Use incx = 1 if the vector x is stored contiguously in

array x; that is, if x

is stored in x(i). Refer to “BLAS

Indexing Conventions” in the introduction to this

chapter.

Output i If n ≤ 0, then i = 0. Otherwise, i is the index of the

element of x of maximum magnitude.