Skip to content
Open
Show file tree
Hide file tree
Changes from all commits
Commits
File filter

Filter by extension

Filter by extension

Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
Original file line number Diff line number Diff line change
Expand Up @@ -42,11 +42,16 @@ Returns the index of the first element in a one-dimensional double-precision flo

```javascript
var Float64Vector = require( '@stdlib/ndarray/vector/float64' );
var scalar2ndarray = require( '@stdlib/ndarray/from-scalar' );

var x = new Float64Vector( [ 0.0, 0.0, 1.0, 0.0 ] );
var y = new Float64Vector( [ 0.0, 0.0, 0.0, 0.0 ] );

var idx = dfirstIndexGreaterThan( [ x, y ] );
var fromIndex = scalar2ndarray( 0, {
'dtype': 'generic'
});

var idx = dfirstIndexGreaterThan( [ x, y, fromIndex ] );
// returns 2
```

Expand All @@ -56,16 +61,22 @@ The function has the following parameters:

- first one-dimensional input ndarray.
- second one-dimensional input ndarray.
- a zero-dimensional ndarray containing the index from which to begin searching.

If the function is unable to find an element in the first one-dimensional input ndarray which is greater than a corresponding element in the second one-dimensional input ndarray, the function returns `-1`.

```javascript
var Float64Vector = require( '@stdlib/ndarray/vector/float64' );
var scalar2ndarray = require( '@stdlib/ndarray/from-scalar' );

var x = new Float64Vector( [ 1.0, 2.0, 3.0, 4.0 ] );
var y = new Float64Vector( [ 5.0, 6.0, 7.0, 8.0 ] );

var idx = dfirstIndexGreaterThan( [ x, y ] );
var fromIndex = scalar2ndarray( 0, {
'dtype': 'generic'
});

var idx = dfirstIndexGreaterThan( [ x, y, fromIndex ] );
// returns -1
```

Expand All @@ -78,6 +89,7 @@ var idx = dfirstIndexGreaterThan( [ x, y ] );
## Notes

- When comparing elements, the function checks whether an element in the first one-dimensional input ndarray is greater than a corresponding element in the second one-dimensional input ndarray using the greater-than operator `>`. As a consequence, comparisons involving `NaN` always evaluate to `false`.
- If a specified starting search index is negative, the function resolves the starting search index by counting backward from the last element (where `-1` refers to the last element).

</section>

Expand All @@ -91,7 +103,9 @@ var idx = dfirstIndexGreaterThan( [ x, y ] );

```javascript
var discreteUniform = require( '@stdlib/random/discrete-uniform' );
var scalar2ndarray = require( '@stdlib/ndarray/from-scalar' );
var ndarray2array = require( '@stdlib/ndarray/to-array' );
var ndarraylike2scalar = require( '@stdlib/ndarray/ndarraylike2scalar' );
var dfirstIndexGreaterThan = require( '@stdlib/blas/ext/base/ndarray/dfirst-index-greater-than' );

var opts = {
Expand All @@ -103,7 +117,12 @@ console.log( ndarray2array( x ) );
var y = discreteUniform( [ 10 ], 0, 10, opts );
console.log( ndarray2array( y ) );

var idx = dfirstIndexGreaterThan( [ x, y ] );
var fromIndex = scalar2ndarray( 0, {
'dtype': 'generic'
});
console.log( 'From Index:', ndarraylike2scalar( fromIndex ) );

var idx = dfirstIndexGreaterThan( [ x, y, fromIndex ] );
console.log( idx );
```

Expand Down
Original file line number Diff line number Diff line change
Expand Up @@ -23,8 +23,8 @@
var bench = require( '@stdlib/bench' );
var isInteger = require( '@stdlib/assert/is-integer' ).isPrimitive;
var pow = require( '@stdlib/math/base/special/pow' );
var Float64Vector = require( '@stdlib/ndarray/vector/float64' );
var ones = require( '@stdlib/array/ones' );
var scalar2ndarray = require( '@stdlib/ndarray/from-scalar' );
var ones = require( '@stdlib/ndarray/ones' );
var format = require( '@stdlib/string/format' );
var pkg = require( './../package.json' ).name;
var dfirstIndexGreaterThan = require( './../lib' );
Expand All @@ -47,8 +47,15 @@ var options = {
* @returns {Function} benchmark function
*/
function createBenchmark( len ) {
var x = new Float64Vector( ones( len, options.dtype ) );
var y = new Float64Vector( ones( len, options.dtype ) );
var fromIndex;
var x;
var y;

x = ones( [ len ], options );
y = ones( [ len ], options );
fromIndex = scalar2ndarray( 0, {
'dtype': 'generic'
});
return benchmark;

/**
Expand All @@ -63,7 +70,7 @@ function createBenchmark( len ) {

b.tic();
for ( i = 0; i < b.iterations; i++ ) {
out = dfirstIndexGreaterThan( [ x, y ] );
out = dfirstIndexGreaterThan( [ x, y, fromIndex ] );
if ( out !== out ) {
b.fail( 'should return an integer' );
}
Expand Down
Original file line number Diff line number Diff line change
Expand Up @@ -10,13 +10,19 @@
`>`. As a consequence, comparisons involving `NaN` always evaluate to
`false`.

If a specified starting search index is negative, the function resolves the
starting search index by counting backward from the last element (where `-1`
refers to the last element).

Parameters
----------
arrays: ArrayLikeObject<ndarray>
Array-like object containing the following ndarrays:

- first one-dimensional input ndarray.
- second one-dimensional input ndarray.
- a zero-dimensional ndarray containing the index from which to begin
searching.

Returns
-------
Expand All @@ -27,7 +33,8 @@
--------
> var x = new {{alias:@stdlib/ndarray/vector/float64}}( [ 0.0, 0.0, 1.0, 0.0 ] );
> var y = new {{alias:@stdlib/ndarray/vector/float64}}( [ 0.0, 0.0, 0.0, 0.0 ] );
> {{alias}}( [ x, y ] )
> var i = {{alias:@stdlib/ndarray/from-scalar}}( 0, { 'dtype': 'generic' } );
> {{alias}}( [ x, y, i ] )
2

See Also
Expand Down
Original file line number Diff line number Diff line change
Expand Up @@ -20,7 +20,7 @@

/// <reference types="@stdlib/types"/>

import { float64ndarray } from '@stdlib/types/ndarray';
import { float64ndarray, typedndarray } from '@stdlib/types/ndarray';

/**
* Returns the index of the first element in a one-dimensional double-precision floating-point ndarray which is greater than a corresponding element in another one-dimensional double-precision floating-point ndarray.
Expand All @@ -31,6 +31,7 @@ import { float64ndarray } from '@stdlib/types/ndarray';
*
* - first one-dimensional input ndarray.
* - second one-dimensional input ndarray.
* - a zero-dimensional ndarray containing the index from which to begin searching.
*
* - When comparing elements, the function checks whether an element in the first one-dimensional input ndarray is greater than a corresponding element in the second one-dimensional input ndarray using the greater-than operator `>`. As a consequence, comparisons involving `NaN` always evaluate to `false`.
*
Expand All @@ -39,14 +40,19 @@ import { float64ndarray } from '@stdlib/types/ndarray';
*
* @example
* var Float64Vector = require( '@stdlib/ndarray/vector/float64' );
* var scalar2ndarray = require( '@stdlib/ndarray/from-scalar' );
*
* var x = new Float64Vector( [ 0.0, 0.0, 1.0, 0.0 ] );
* var y = new Float64Vector( [ 0.0, 0.0, 0.0, 0.0 ] );
*
* var idx = dfirstIndexGreaterThan( [ x, y ] );
* var fromIndex = scalar2ndarray( 0, {
* 'dtype': 'generic'
* });
*
* var idx = dfirstIndexGreaterThan( [ x, y, fromIndex ] );
* // returns 2
*/
declare function dfirstIndexGreaterThan( arrays: [ float64ndarray, float64ndarray ] ): number;
declare function dfirstIndexGreaterThan( arrays: [ float64ndarray, float64ndarray, typedndarray<number> ] ): number;


// EXPORTS //
Expand Down
Original file line number Diff line number Diff line change
Expand Up @@ -19,6 +19,7 @@
/* eslint-disable space-in-parens */

import zeros = require( '@stdlib/ndarray/zeros' );
import scalar2ndarray = require( '@stdlib/ndarray/from-scalar' );
import dfirstIndexGreaterThan = require( './index' );


Expand All @@ -32,8 +33,11 @@ import dfirstIndexGreaterThan = require( './index' );
const y = zeros( [ 10 ], {
'dtype': 'float64'
});
const fromIndex = scalar2ndarray( 0, {
'dtype': 'generic'
});

dfirstIndexGreaterThan( [ x, y ] ); // $ExpectType number
dfirstIndexGreaterThan( [ x, y, fromIndex ] ); // $ExpectType number
}

// The compiler throws an error if the function is provided a first argument which is not an array of ndarrays...
Expand All @@ -57,7 +61,10 @@ import dfirstIndexGreaterThan = require( './index' );
const y = zeros( [ 10 ], {
'dtype': 'float64'
});
const fromIndex = scalar2ndarray( 0, {
'dtype': 'generic'
});

dfirstIndexGreaterThan(); // $ExpectError
dfirstIndexGreaterThan( [ x, y ], {} ); // $ExpectError
dfirstIndexGreaterThan( [ x, y, fromIndex ], {} ); // $ExpectError
}
Original file line number Diff line number Diff line change
Expand Up @@ -19,7 +19,9 @@
'use strict';

var discreteUniform = require( '@stdlib/random/discrete-uniform' );
var scalar2ndarray = require( '@stdlib/ndarray/from-scalar' );
var ndarray2array = require( '@stdlib/ndarray/to-array' );
var ndarraylike2scalar = require( '@stdlib/ndarray/ndarraylike2scalar' );
var dfirstIndexGreaterThan = require( './../lib' );

var opts = {
Expand All @@ -31,5 +33,10 @@ console.log( ndarray2array( x ) );
var y = discreteUniform( [ 10 ], 0, 10, opts );
console.log( ndarray2array( y ) );

var idx = dfirstIndexGreaterThan( [ x, y ] );
var fromIndex = scalar2ndarray( 0, {
'dtype': 'generic'
});
console.log( 'From Index:', ndarraylike2scalar( fromIndex ) );

var idx = dfirstIndexGreaterThan( [ x, y, fromIndex ] );
console.log( idx );
Original file line number Diff line number Diff line change
Expand Up @@ -25,12 +25,17 @@
*
* @example
* var Float64Vector = require( '@stdlib/ndarray/vector/float64' );
* var scalar2ndarray = require( '@stdlib/ndarray/from-scalar' );
* var dfirstIndexGreaterThan = require( '@stdlib/blas/ext/base/ndarray/dfirst-index-greater-than' );
*
* var x = new Float64Vector( [ 0.0, 0.0, 1.0, 0.0 ] );
* var y = new Float64Vector( [ 0.0, 0.0, 0.0, 0.0 ] );
*
* var idx = dfirstIndexGreaterThan( [ x, y ] );
* var fromIndex = scalar2ndarray( 0, {
* 'dtype': 'generic'
* });
*
* var idx = dfirstIndexGreaterThan( [ x, y, fromIndex ] );
* // returns 2
*/

Expand Down
Original file line number Diff line number Diff line change
Expand Up @@ -25,6 +25,7 @@ var getStride = require( '@stdlib/ndarray/base/stride' );
var getOffset = require( '@stdlib/ndarray/base/offset' );
var getData = require( '@stdlib/ndarray/base/data-buffer' );
var strided = require( '@stdlib/blas/ext/base/dfirst-index-greater-than' ).ndarray;
var ndarraylike2scalar = require( '@stdlib/ndarray/base/ndarraylike2scalar' );


// MAIN //
Expand All @@ -38,6 +39,7 @@ var strided = require( '@stdlib/blas/ext/base/dfirst-index-greater-than' ).ndarr
*
* - first one-dimensional input ndarray.
* - second one-dimensional input ndarray.
* - a zero-dimensional ndarray containing the index from which to begin searching.
*
* - When comparing elements, the function checks whether an element in the first one-dimensional input ndarray is greater than a corresponding element in the second one-dimensional input ndarray using the greater-than operator `>`. As a consequence, comparisons involving `NaN` always evaluate to `false`.
*
Expand All @@ -46,17 +48,53 @@ var strided = require( '@stdlib/blas/ext/base/dfirst-index-greater-than' ).ndarr
*
* @example
* var Float64Vector = require( '@stdlib/ndarray/vector/float64' );
* var scalar2ndarray = require( '@stdlib/ndarray/from-scalar' );
*
* var x = new Float64Vector( [ 0.0, 0.0, 1.0, 0.0 ] );
* var y = new Float64Vector( [ 0.0, 0.0, 0.0, 0.0 ] );
*
* var idx = dfirstIndexGreaterThan( [ x, y ] );
* var fromIndex = scalar2ndarray( 0, {
* 'dtype': 'generic'
* });
*
* var idx = dfirstIndexGreaterThan( [ x, y, fromIndex ] );
* // returns 2
*/
function dfirstIndexGreaterThan( arrays ) {
var x = arrays[ 0 ];
var y = arrays[ 1 ];
return strided( numelDimension( x, 0 ), getData( x ), getStride( x, 0 ), getOffset( x ), getData( y ), getStride( y, 0 ), getOffset( y ) ); // eslint-disable-line max-len
var fromIndex;
var idx;
var sx;
var sy;
var ox;
var oy;
var N;
var x;
var y;

x = arrays[ 0 ];
y = arrays[ 1 ];
N = numelDimension( x, 0 );
fromIndex = ndarraylike2scalar( arrays[ 2 ] );

if ( fromIndex < 0 ) {
fromIndex += N;
if ( fromIndex < 0 ) {
fromIndex = 0;
}
} else if ( fromIndex >= N ) {
return -1;
}
N -= fromIndex;
sx = getStride( x, 0 );
ox = getOffset( x ) + ( sx*fromIndex );
sy = getStride( y, 0 );
oy = getOffset( y ) + ( sy*fromIndex );

idx = strided( N, getData( x ), sx, ox, getData( y ), sy, oy );
if ( idx >= 0 ) {
idx += fromIndex;
}
return idx;
}


Expand Down
Loading