Skip to content

Commit 4af2747

Browse files
kgrytekgryte
committed
Add strided interface to fill a single-precision floating-point strided array with a scalar constant
1 parent 4182f5d commit 4af2747

33 files changed

+3476
-0
lines changed

‎lib/node_modules/@stdlib/blas/ext/base/sfill/README.md

+172
Original file line numberDiff line numberDiff line change
@@ -0,0 +1,172 @@
1+
<!--
2+
3+
@license Apache-2.0
4+
5+
Copyright (c) 2020 The Stdlib Authors.
6+
7+
Licensed under the Apache License, Version 2.0 (the "License");
8+
you may not use this file except in compliance with the License.
9+
You may obtain a copy of the License at
10+
11+
http://www.apache.org/licenses/LICENSE-2.0
12+
13+
Unless required by applicable law or agreed to in writing, software
14+
distributed under the License is distributed on an "AS IS" BASIS,
15+
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
16+
See the License for the specific language governing permissions and
17+
limitations under the License.
18+
19+
-->
20+
21+
# sfill
22+
23+
> Fill a single-precision floating-point strided array with a specified scalar constant.
24+
25+
<section class="usage">
26+
27+
## Usage
28+
29+
```javascript
30+
var sfill = require( '@stdlib/blas/ext/base/sfill' );
31+
```
32+
33+
#### sfill( N, alpha, x, stride )
34+
35+
Fills a single-precision floating-point strided array `x` with a specified scalar constant `alpha`.
36+
37+
```javascript
38+
var Float32Array = require( '@stdlib/array/float32' );
39+
40+
var x = new Float32Array( [ -2.0, 1.0, 3.0, -5.0, 4.0, 0.0, -1.0, -3.0 ] );
41+
42+
sfill( x.length, 5.0, x, 1 );
43+
// x => <Float32Array>[ 5.0, 5.0, 5.0, 5.0, 5.0, 5.0, 5.0, 5.0 ]
44+
```
45+
46+
The function has the following parameters:
47+
48+
- **N**: number of indexed elements.
49+
- **alpha**: scalar constant.
50+
- **x**: input [`Float32Array`][@stdlib/array/float32].
51+
- **stride**: index increment.
52+
53+
The `N` and `stride` parameters determine which elements in `x` are accessed at runtime. For example, to fill every other element
54+
55+
```javascript
56+
var Float32Array = require( '@stdlib/array/float32' );
57+
var floor = require( '@stdlib/math/base/special/floor' );
58+
59+
var x = new Float32Array( [ -2.0, 1.0, 3.0, -5.0, 4.0, 0.0, -1.0, -3.0 ] );
60+
var N = floor( x.length / 2 );
61+
62+
sfill( N, 5.0, x, 2 );
63+
// x => <Float32Array>[ 5.0, 1.0, 5.0, -5.0, 5.0, 0.0, 5.0, -3.0 ]
64+
```
65+
66+
Note that indexing is relative to the first index. To introduce an offset, use [`typed array`][mdn-typed-array] views.
67+
68+
```javascript
69+
var Float32Array = require( '@stdlib/array/float32' );
70+
var floor = require( '@stdlib/math/base/special/floor' );
71+
72+
// Initial array...
73+
var x0 = new Float32Array( [ 1.0, -2.0, 3.0, -4.0, 5.0, -6.0 ] );
74+
75+
// Create an offset view...
76+
var x1 = new Float32Array( x0.buffer, x0.BYTES_PER_ELEMENT*1 ); // start at 2nd element
77+
var N = floor( x0.length/2 );
78+
79+
// Fill every other element...
80+
sfill( N, 5.0, x1, 2 );
81+
// x0 => <Float32Array>[ 1.0, 5.0, 3.0, 5.0, 5.0, 5.0 ]
82+
```
83+
84+
#### sfill.ndarray( N, alpha, x, stride, offset )
85+
86+
Fills a single-precision floating-point strided array `x` with a specified scalar constant `alpha` using alternative indexing semantics.
87+
88+
```javascript
89+
var Float32Array = require( '@stdlib/array/float32' );
90+
91+
var x = new Float32Array( [ -2.0, 1.0, 3.0, -5.0, 4.0, 0.0, -1.0, -3.0 ] );
92+
93+
sfill.ndarray( x.length, 5.0, x, 1, 0 );
94+
// x => <Float32Array>[ 5.0, 5.0, 5.0, 5.0, 5.0, 5.0, 5.0, 5.0 ]
95+
```
96+
97+
The function has the following additional parameters:
98+
99+
- **offset**: starting index.
100+
101+
While [`typed array`][mdn-typed-array] views mandate a view offset based on the underlying `buffer`, the `offset` parameter supports indexing semantics based on a starting index. For example, to access only the last three elements of `x`
102+
103+
```javascript
104+
var Float32Array = require( '@stdlib/array/float32' );
105+
106+
var x = new Float32Array( [ 1.0, -2.0, 3.0, -4.0, 5.0, -6.0 ] );
107+
108+
sfill.ndarray( 3, 5.0, x, 1, x.length-3 );
109+
// x => <Float32Array>[ 1.0, -2.0, 3.0, 5.0, 5.0, 5.0 ]
110+
```
111+
112+
</section>
113+
114+
<!-- /.usage -->
115+
116+
<section class="notes">
117+
118+
## Notes
119+
120+
- If `N <= 0`, both functions return `x` unchanged.
121+
122+
</section>
123+
124+
<!-- /.notes -->
125+
126+
<section class="examples">
127+
128+
## Examples
129+
130+
<!-- eslint no-undef: "error" -->
131+
132+
```javascript
133+
var round = require( '@stdlib/math/base/special/round' );
134+
var randu = require( '@stdlib/random/base/randu' );
135+
var Float32Array = require( '@stdlib/array/float32' );
136+
var sfill = require( '@stdlib/blas/ext/base/sfill' );
137+
138+
var rand;
139+
var sign;
140+
var x;
141+
var i;
142+
143+
x = new Float32Array( 10 );
144+
for ( i = 0; i < x.length; i++ ) {
145+
rand = round( randu()*100.0 );
146+
sign = randu();
147+
if ( sign < 0.5 ) {
148+
sign = -1.0;
149+
} else {
150+
sign = 1.0;
151+
}
152+
x[ i ] = sign * rand;
153+
}
154+
console.log( x );
155+
156+
sfill( x.length, 5.0, x, 1 );
157+
console.log( x );
158+
```
159+
160+
</section>
161+
162+
<!-- /.examples -->
163+
164+
<section class="links">
165+
166+
[@stdlib/array/float32]: https://github.com/stdlib-js/stdlib
167+
168+
[mdn-typed-array]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray
169+
170+
</section>
171+
172+
<!-- /.links -->

‎lib/node_modules/@stdlib/blas/ext/base/sfill/benchmark/benchmark.js

+91
Original file line numberDiff line numberDiff line change
@@ -0,0 +1,91 @@
1+
/**
2+
* @license Apache-2.0
3+
*
4+
* Copyright (c) 2020 The Stdlib Authors.
5+
*
6+
* Licensed under the Apache License, Version 2.0 (the "License");
7+
* you may not use this file except in compliance with the License.
8+
* You may obtain a copy of the License at
9+
*
10+
* http://www.apache.org/licenses/LICENSE-2.0
11+
*
12+
* Unless required by applicable law or agreed to in writing, software
13+
* distributed under the License is distributed on an "AS IS" BASIS,
14+
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
15+
* See the License for the specific language governing permissions and
16+
* limitations under the License.
17+
*/
18+
19+
'use strict';
20+
21+
// MODULES //
22+
23+
var bench = require( '@stdlib/bench' );
24+
var randu = require( '@stdlib/random/base/randu' );
25+
var isnanf = require( '@stdlib/math/base/assert/is-nanf' );
26+
var pow = require( '@stdlib/math/base/special/pow' );
27+
var Float32Array = require( '@stdlib/array/float32' );
28+
var pkg = require( './../package.json' ).name;
29+
var sfill = require( './../lib/sfill.js' );
30+
31+
32+
// FUNCTIONS //
33+
34+
/**
35+
* Create a benchmark function.
36+
*
37+
* @private
38+
* @param {PositiveInteger} len - array length
39+
* @returns {Function} benchmark function
40+
*/
41+
function createBenchmark( len ) {
42+
var x;
43+
var i;
44+
45+
x = new Float32Array( len );
46+
for ( i = 0; i < len; i++ ) {
47+
x[ i ] = ( randu()*20.0 ) - 10.0;
48+
}
49+
return benchmark;
50+
51+
function benchmark( b ) {
52+
var y;
53+
var i;
54+
55+
b.tic();
56+
for ( i = 0; i < b.iterations; i++ ) {
57+
y = sfill( x.length, i, x, 1 );
58+
if ( isnanf( y[ i%x.length ] ) ) {
59+
b.fail( 'should not return NaN' );
60+
}
61+
}
62+
b.toc();
63+
if ( isnanf( y[ i%x.length ] ) ) {
64+
b.fail( 'should not return NaN' );
65+
}
66+
b.pass( 'benchmark finished' );
67+
b.end();
68+
}
69+
}
70+
71+
72+
// MAIN //
73+
74+
function main() {
75+
var len;
76+
var min;
77+
var max;
78+
var f;
79+
var i;
80+
81+
min = 1; // 10^min
82+
max = 6; // 10^max
83+
84+
for ( i = min; i <= max; i++ ) {
85+
len = pow( 10, i );
86+
f = createBenchmark( len );
87+
bench( pkg+':len='+len, f );
88+
}
89+
}
90+
91+
main();

‎lib/node_modules/@stdlib/blas/ext/base/sfill/benchmark/benchmark.native.js

+100
Original file line numberDiff line numberDiff line change
@@ -0,0 +1,100 @@
1+
/**
2+
* @license Apache-2.0
3+
*
4+
* Copyright (c) 2020 The Stdlib Authors.
5+
*
6+
* Licensed under the Apache License, Version 2.0 (the "License");
7+
* you may not use this file except in compliance with the License.
8+
* You may obtain a copy of the License at
9+
*
10+
* http://www.apache.org/licenses/LICENSE-2.0
11+
*
12+
* Unless required by applicable law or agreed to in writing, software
13+
* distributed under the License is distributed on an "AS IS" BASIS,
14+
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
15+
* See the License for the specific language governing permissions and
16+
* limitations under the License.
17+
*/
18+
19+
'use strict';
20+
21+
// MODULES //
22+
23+
var resolve = require( 'path' ).resolve;
24+
var bench = require( '@stdlib/bench' );
25+
var randu = require( '@stdlib/random/base/randu' );
26+
var isnanf = require( '@stdlib/math/base/assert/is-nanf' );
27+
var pow = require( '@stdlib/math/base/special/pow' );
28+
var Float32Array = require( '@stdlib/array/float32' );
29+
var tryRequire = require( '@stdlib/utils/try-require' );
30+
var pkg = require( './../package.json' ).name;
31+
32+
33+
// VARIABLES //
34+
35+
var sfill = tryRequire( resolve( __dirname, './../lib/native.js' ) );
36+
var opts = {
37+
'skip': ( sfill instanceof Error )
38+
};
39+
40+
41+
// FUNCTIONS //
42+
43+
/**
44+
* Create a benchmark function.
45+
*
46+
* @private
47+
* @param {PositiveInteger} len - array length
48+
* @returns {Function} benchmark function
49+
*/
50+
function createBenchmark( len ) {
51+
var x;
52+
var i;
53+
54+
x = new Float32Array( len );
55+
for ( i = 0; i < len; i++ ) {
56+
x[ i ] = ( randu()*20.0 ) - 10.0;
57+
}
58+
return benchmark;
59+
60+
function benchmark( b ) {
61+
var y;
62+
var i;
63+
64+
b.tic();
65+
for ( i = 0; i < b.iterations; i++ ) {
66+
y = sfill( x.length, i, x, 1 );
67+
if ( isnanf( y[ i%x.length ] ) ) {
68+
b.fail( 'should not return NaN' );
69+
}
70+
}
71+
b.toc();
72+
if ( isnanf( y[ i%x.length ] ) ) {
73+
b.fail( 'should not return NaN' );
74+
}
75+
b.pass( 'benchmark finished' );
76+
b.end();
77+
}
78+
}
79+
80+
81+
// MAIN //
82+
83+
function main() {
84+
var len;
85+
var min;
86+
var max;
87+
var f;
88+
var i;
89+
90+
min = 1; // 10^min
91+
max = 6; // 10^max
92+
93+
for ( i = min; i <= max; i++ ) {
94+
len = pow( 10, i );
95+
f = createBenchmark( len );
96+
bench( pkg+'::native:len='+len, opts, f );
97+
}
98+
}
99+
100+
main();

0 commit comments

Comments
 (0)