Developer Reference for Intel® oneAPI Math Kernel Library for Fortran

ID 766686
Date 11/07/2023
Public

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i?amin

Finds the index of the element with the smallest absolute value.

Syntax

index = isamin(n, x, incx)

index = idamin(n, x, incx)

index = icamin(n, x, incx)

index = izamin(n, x, incx)

index = iamin(x)

Include Files

  • mkl.fi, blas.f90

Description

Given a vector x, the i?amin functions return the position of the vector element x[i] that has the smallest absolute value for real flavors, or the smallest sum |Re(x[i])|+|Im(x[i])| for complex flavors.

If either n or incx are not positive, the routine returns 0.

If more than one vector element is found with the same smallest absolute value, the index of the first one encountered is returned.

If the vector contains NaN values, then the routine returns the index of the first NaN.

Input Parameters

n

INTEGER. On entry, n specifies the number of elements in vector x.

x

REAL for isamin

DOUBLE PRECISION for idamin

COMPLEX for icamin

DOUBLE COMPLEX for izamin

Array, size at least (1+(n-1)*abs(incx)).

incx

INTEGER. Specifies the increment for the elements of x.

Output Parameters

index

INTEGER. Indicates the position of vector element with the smallest absolute value such that x(index) has the smallest absolute value.

BLAS 95 Interface Notes

Functions and routines in Fortran 95 interface have fewer arguments in the calling sequence than their FORTRAN 77 counterparts. For general conventions applied to skip redundant or reconstructible arguments, see BLAS 95 Interface Conventions.

Specific details for the function iamin interface are the following:

x

Holds the vector with the number of elements n.