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Return the index of the first row in a double-precision floating-point input matrix which has the same elements as a provided search vector.
npm install @stdlib/blas-ext-base-dindex-of-rowAlternatively,
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var dindexOfRow = require( '@stdlib/blas-ext-base-dindex-of-row' );Returns the index of the first row in a double-precision floating-point input matrix which has the same elements as a provided search vector.
var Float64Array = require( '@stdlib/array-float64' );
var Uint8Array = require( '@stdlib/array-uint8' );
/*
A = [
[ 1.0, 3.0 ],
[ 2.0, 4.0 ],
[ 0.0, 0.0 ]
]
*/
var A = new Float64Array( [ 1.0, 2.0, 0.0, 3.0, 4.0, 0.0 ] );
var x = new Float64Array( [ 2.0, 4.0 ] );
var workspace = new Uint8Array( 3 );
var out = dindexOfRow( 'column-major', 3, 2, A, 3, x, 1, workspace, 1 );
// returns 1The function has the following parameters:
- order: storage layout.
- M: number of rows in
A. - N: number of columns in
A. - A: input matrix stored as a
Float64Array. - LDA: stride of the first dimension of
A(a.k.a., leading dimension of the matrixA). - x: search vector stored as a
Float64Array. - strideX: stride length of
x. - workspace: workspace array stored as a
Uint8Arrayfor tracking row match candidates. This parameter is ignored if the function is provided an input matrix stored in row-major order. - strideW: stride length of
workspace.
When an input matrix is stored in row-major order, the workspace parameter is ignored, and, thus, one may provide an empty workspace array.
var Float64Array = require( '@stdlib/array-float64' );
var Uint8Array = require( '@stdlib/array-uint8' );
/*
A = [
[ 1.0, 2.0 ],
[ 3.0, 4.0 ],
[ 0.0, 0.0 ]
]
*/
var A = new Float64Array( [ 1.0, 2.0, 3.0, 4.0, 0.0, 0.0 ] );
var x = new Float64Array( [ 3.0, 4.0 ] );
var workspace = new Uint8Array( 0 );
var out = dindexOfRow( 'row-major', 3, 2, A, 2, x, 1, workspace, 1 );
// returns 1If the function is unable to find a matching row, the function returns -1.
var Float64Array = require( '@stdlib/array-float64' );
var Uint8Array = require( '@stdlib/array-uint8' );
/*
A = [
[ 1.0, 3.0 ],
[ 2.0, 4.0 ],
[ 0.0, 0.0 ]
]
*/
var A = new Float64Array( [ 1.0, 2.0, 0.0, 3.0, 4.0, 0.0 ] );
var x = new Float64Array( [ -3.0, -4.0 ] );
var workspace = new Uint8Array( 3 );
var out = dindexOfRow( 'column-major', 3, 2, A, 3, x, 1, workspace, 1 );
// returns -1Note that indexing is relative to the first index. To introduce an offset, use typed array views.
var Float64Array = require( '@stdlib/array-float64' );
var Uint8Array = require( '@stdlib/array-uint8' );
// Initial arrays:
var A0 = new Float64Array( [ 0.0, 1.0, 2.0, 3.0, 4.0, 0.0, 0.0 ] );
var x0 = new Float64Array( [ 0.0, 3.0, 4.0 ] );
// Create offset views:
var A1 = new Float64Array( A0.buffer, A0.BYTES_PER_ELEMENT*1 ); // start at 2nd element
var x1 = new Float64Array( x0.buffer, x0.BYTES_PER_ELEMENT*1 ); // start at 2nd element
var workspace = new Uint8Array( 0 );
var out = dindexOfRow( 'row-major', 3, 2, A1, 2, x1, 1, workspace, 1 );
// returns 1dindexOfRow.ndarray( M, N, A, strideA1, strideA2, offsetA, x, strideX, offsetX, workspace, strideW, offsetW )
Returns the index of the first row in a double-precision floating-point input matrix which has the same elements as a provided search vector using alternative indexing semantics.
var Float64Array = require( '@stdlib/array-float64' );
var Uint8Array = require( '@stdlib/array-uint8' );
/*
A = [
[ 1.0, 3.0 ],
[ 2.0, 4.0 ],
[ 0.0, 0.0 ]
]
*/
var A = new Float64Array( [ 1.0, 2.0, 0.0, 3.0, 4.0, 0.0 ] );
var x = new Float64Array( [ 2.0, 4.0 ] );
var workspace = new Uint8Array( 3 );
var out = dindexOfRow.ndarray( 3, 2, A, 1, 3, 0, x, 1, 0, workspace, 1, 0 );
// returns 1The function has the following parameters:
- M: number of rows in
A. - N: number of columns in
A. - A: input matrix stored as a
Float64Array. - strideA1: stride of the first dimension of
A. - strideA2: stride of the second dimension of
A. - offsetA: starting index for
A. - x: search vector stored as a
Float64Array. - strideX: stride length of
x. - offsetX: starting index for
x. - workspace: workspace array stored as a
Uint8Arrayfor tracking row match candidates. This parameter is ignored if the function is provided an input matrix stored in row-major order. - strideW: stride length of
workspace. - offsetW: starting index for
workspace.
When an input matrix is stored in row-major order, the workspace parameter is ignored, and, thus, one may provide an empty workspace array.
var Float64Array = require( '@stdlib/array-float64' );
var Uint8Array = require( '@stdlib/array-uint8' );
var A = new Float64Array( [ 1.0, 2.0, 3.0, 4.0, 0.0, 0.0 ] );
var x = new Float64Array( [ 3.0, 4.0 ] );
var workspace = new Uint8Array( 0 );
var out = dindexOfRow.ndarray( 3, 2, A, 2, 1, 0, x, 1, 0, workspace, 1, 0 );
// returns 1- When searching for a matching row, the function checks for equality using the strict equality operator
===. As a consequence,NaNvalues are considered distinct, and-0and+0are considered the same.
var Float64Array = require( '@stdlib/array-float64' );
var Uint8Array = require( '@stdlib/array-uint8' );
var ndarray2array = require( '@stdlib/ndarray-base-to-array' );
var shape2strides = require( '@stdlib/ndarray-base-shape2strides' );
var dindexOfRow = require( '@stdlib/blas-ext-base-dindex-of-row' );
var shape = [ 3, 3 ];
var order = 'row-major';
var strides = shape2strides( shape, order );
var A = new Float64Array( [ 1.0, 2.0, 3.0, 4.0, 5.0, 6.0, 0.0, 0.0, 0.0 ] );
console.log( ndarray2array( A, shape, strides, 0, order ) );
var x = new Float64Array( [ 4.0, 5.0, 6.0 ] );
console.log( x );
var workspace = new Uint8Array( shape[ 0 ] );
var out = dindexOfRow( order, shape[ 0 ], shape[ 1 ], A, strides[ 0 ], x, 1, workspace, 1 );
console.log( out );#include "stdlib/blas/ext/base/dindex_of_row.h"Returns the index of the first row in a double-precision floating-point input matrix which has the same elements as a provided search vector.
#include "stdlib/blas/base/shared.h"
#include <stdint.h>
const double A[] = { 1.0, 2.0, 0.0, 3.0, 4.0, 0.0 };
const double x[] = { 2.0, 4.0 };
uint8_t workspace[ 3 ];
int idx = stdlib_strided_dindex_of_row( CblasColMajor, 3, 2, A, 3, x, 1, workspace, 1 );
// returns 1The function accepts the following arguments:
- order:
[in] CBLAS_LAYOUTstorage layout. - M:
[in] CBLAS_INTnumber of rows inA. - N:
[in] CBLAS_INTnumber of columns inA. - A:
[in] double*input matrix. - LDA:
[in] CBLAS_INTstride of the first dimension ofA(a.k.a., leading dimension of the matrixA). - X:
[in] double*search vector. - strideX:
[in] CBLAS_INTstride length forX. - workspace:
[inout] uint8_t*workspace array for tracking row match candidates. This parameter is ignored if the function is provided an input matrix stored in row-major order. - strideW:
[in] CBLAS_INTstride length forworkspace.
When an input matrix is stored in row-major order, the workspace parameter is ignored, and, thus, one may either provide an empty workspace array or a NULL pointer.
#include "stdlib/blas/base/shared.h"
const double A[] = { 1.0, 2.0, 3.0, 4.0, 0.0, 0.0 };
const double x[] = { 3.0, 4.0 };
int idx = stdlib_strided_dindex_of_row( CblasRowMajor, 3, 2, A, 2, x, 1, NULL, 1 );
// returns 1CBLAS_INT stdlib_strided_dindex_of_row( const CBLAS_LAYOUT order, const CBLAS_INT M, const CBLAS_INT N, const double *A, const CBLAS_INT LDA, const double *X, const CBLAS_INT strideX, uint8_t *workspace, const CBLAS_INT strideW );stdlib_strided_dindex_of_row_ndarray( M, N, *A, strideA1, strideA2, offsetA, *X, strideX, offsetX, *workspace, strideW, offsetW )
Returns the index of the first row in a double-precision floating-point input matrix which has the same elements as a provided search vector using alternative indexing semantics.
#include <stdint.h>
const double A[] = { 1.0, 2.0, 0.0, 3.0, 4.0, 0.0 };
const double x[] = { 2.0, 4.0 };
uint8_t workspace[ 3 ];
int idx = stdlib_strided_dindex_of_row_ndarray( 3, 2, A, 1, 3, 0, x, 1, 0, workspace, 1, 0 );
// returns 1The function accepts the following arguments:
- M:
[in] CBLAS_INTnumber of rows inA. - N:
[in] CBLAS_INTnumber of columns inA. - A:
[in] double*input matrix. - strideA1:
[in] CBLAS_INTstride of the first dimension ofA. - strideA2:
[in] CBLAS_INTstride of the second dimension ofA. - offsetA:
[in] CBLAS_INTindex offset forA. - X:
[in] double*search vector. - strideX:
[in] CBLAS_INTstride length forX. - offsetX:
[in] CBLAS_INTstarting index forX. - workspace:
[inout] uint8_t*workspace array for tracking row match candidates. This parameter is ignored if the function is provided an input matrix stored in row-major order. - strideW:
[in] CBLAS_INTstride length forworkspace. - offsetW:
[in] CBLAS_INTstarting index forworkspace.
When an input matrix is stored in row-major order, the workspace parameter is ignored, and, thus, one may either provide an empty workspace array or a NULL pointer.
const double A[] = { 1.0, 2.0, 3.0, 4.0, 0.0, 0.0 };
const double x[] = { 3.0, 4.0 };
int idx = stdlib_strided_dindex_of_row_ndarray( 3, 2, A, 2, 1, 0, x, 1, 0, NULL, 1, 0 );
// returns 1CBLAS_INT stdlib_strided_dindex_of_row_ndarray( const CBLAS_INT M, const CBLAS_INT N, const double *A, const CBLAS_INT strideA1, const CBLAS_INT strideA2, const CBLAS_INT offsetA, const double *X, const CBLAS_INT strideX, const CBLAS_INT offsetX, uint8_t *workspace, const CBLAS_INT strideW, const CBLAS_INT offsetW );#include "stdlib/blas/ext/base/dindex_of_row.h"
#include "stdlib/blas/base/shared.h"
#include <stdio.h>
int main( void ) {
// Create a matrix (row-major):
const double A[] = { 1.0, 2.0, 3.0, 4.0, 5.0, 6.0, 0.0, 0.0, 0.0 };
// Create a search vector:
const double x[] = { 4.0, 5.0, 6.0 };
// Specify the number of matrix rows and columns:
const int M = 3;
const int N = 3;
// Perform a search:
int idx = stdlib_strided_dindex_of_row( CblasRowMajor, M, N, A, N, x, 1, NULL, 1 );
// Print the result:
printf( "index value: %d\n", idx );
}This package is part of stdlib, a standard library for JavaScript and Node.js, with an emphasis on numerical and scientific computing. The library provides a collection of robust, high performance libraries for mathematics, statistics, streams, utilities, and more.
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