Developer Reference for Intel® oneAPI Math Kernel Library for C

ID 766684
Date 11/07/2023
Public

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Document Table of Contents

df?QueryIdxPtr

Reads a pointer to the memory representing a coordinate of the data stored in matrix format.

Syntax

status = dfsQueryIdxPtr(task, ptr_attr, idx, ptr)

status = dfdQueryIdxPtr(task, ptr_attr, idx, ptr)

Include Files

  • mkl.h

Input Parameters

Name

Type

Description

task

DFTaskPtr

Descriptor of the task.

ptr_attr

const MKL_INT

Pointer attribute to query. The parameter takes one of the attributes described in "Data Attributes Supported by the df?EditIdxPtr Task Editor".

idx

const MKL_INT

Index of the coordinate of the pointer to query.

Output Parameters

Name

Type

Description

ptr

float* for dfsQueryIdxPtr

double* for dfdQueryIdxPtr

Pointer to the data that holds values of coordinate idx returned. For details, see table "Data Attributes Supported by the df?EditIdxPtr Task Editor".

status

int

Status of the routine:

Description

The routine returns a pointer to the array that holds the idx coordinate of vector-valued function y or the pointer to the array of spline coefficients corresponding to the given coordinate.

You can use the query routine if you need the pointer to coordinates of the vector-valued function or spline coefficients held at non-contiguous memory locations or at a contiguous memory location in row-major format (the default storage format for spline coefficients).

Before calling this query routine, make sure that you have created and initialized the task using a task creation function or a relevant editor such as the generic or specific df?EditPPSpline1D editor.

When using df?QueryIdxPtr, you might receive an error code in the following cases:

  • You passed an unsupported parameter value into the editor.

  • The value of the index exceeds the predefined value that equals the dimension ny of the vector-valued function.

  • You request the pointer to the idx coordinate of the vector-valued function you provided to contiguous memory in column-major format.