Skip to content

Commit 59a367b

Browse files
committed
feat: add stats/strided/smediansorted
Ref: #4797 --- type: pre_commit_static_analysis_report description: Results of running static analysis checks when committing changes. report: - task: lint_filenames status: passed - task: lint_editorconfig status: passed - task: lint_markdown status: passed - task: lint_package_json status: passed - task: lint_repl_help status: passed - task: lint_javascript_src status: passed - task: lint_javascript_cli status: na - task: lint_javascript_examples status: passed - task: lint_javascript_tests status: passed - task: lint_javascript_benchmarks status: passed - task: lint_python status: na - task: lint_r status: na - task: lint_c_src status: passed - task: lint_c_examples status: passed - task: lint_c_benchmarks status: passed - task: lint_c_tests_fixtures status: na - task: lint_shell status: na - task: lint_typescript_declarations status: passed - task: lint_typescript_tests status: passed - task: lint_license_headers status: passed ---
1 parent 04b4549 commit 59a367b

33 files changed

+3418
-0
lines changed
Original file line numberDiff line numberDiff line change
@@ -0,0 +1,306 @@
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+
# smediansorted
22+
23+
> Calculate the median value of a sorted single-precision floating-point strided array.
24+
25+
<section class="intro">
26+
27+
</section>
28+
29+
<!-- /.intro -->
30+
31+
<section class="usage">
32+
33+
## Usage
34+
35+
```javascript
36+
var smediansorted = require( '@stdlib/stats/strided/smediansorted' );
37+
```
38+
39+
#### smediansorted( N, x, strideX )
40+
41+
Computes the median value of a sorted single-precision floating-point strided array `x`.
42+
43+
```javascript
44+
var Float32Array = require( '@stdlib/array/float32' );
45+
46+
var x = new Float32Array( [ 1.0, 2.0, 3.0 ] );
47+
var v = smediansorted( x.length, x, 1 );
48+
// returns 2.0
49+
50+
x = new Float32Array( [ 3.0, 2.0, 1.0 ] );
51+
v = smediansorted( x.length, x, 1 );
52+
// returns 2.0
53+
```
54+
55+
The function has the following parameters:
56+
57+
- **N**: number of indexed elements.
58+
- **x**: sorted input [`Float32Array`][@stdlib/array/float32].
59+
- **strideX**: stride length for `x`.
60+
61+
The `N` and stride parameters determine which elements in the strided array are accessed at runtime. For example, to compute the median value of every other element in `x`,
62+
63+
```javascript
64+
var Float32Array = require( '@stdlib/array/float32' );
65+
66+
var x = new Float32Array( [ 1.0, 2.0, 2.0, -7.0, 3.0, 3.0, 4.0, 2.0 ] );
67+
68+
var v = smediansorted( 4, x, 2 );
69+
// returns 2.5
70+
```
71+
72+
Note that indexing is relative to the first index. To introduce an offset, use [`typed array`][mdn-typed-array] views.
73+
74+
<!-- eslint-disable stdlib/capitalized-comments -->
75+
76+
```javascript
77+
var Float32Array = require( '@stdlib/array/float32' );
78+
79+
var x0 = new Float32Array( [ 2.0, 1.0, 2.0, 2.0, -2.0, 2.0, 3.0, 4.0 ] );
80+
var x1 = new Float32Array( x0.buffer, x0.BYTES_PER_ELEMENT*1 ); // start at 2nd element
81+
82+
var v = smediansorted( 4, x1, 2 );
83+
// returns 2.0
84+
```
85+
86+
#### smediansorted.ndarray( N, x, strideX, offsetX )
87+
88+
Computes the median value of a sorted single-precision floating-point strided array using alternative indexing semantics.
89+
90+
```javascript
91+
var Float32Array = require( '@stdlib/array/float32' );
92+
93+
var x = new Float32Array( [ 1.0, 2.0, 3.0 ] );
94+
95+
var v = smediansorted.ndarray( x.length, x, 1, 0 );
96+
// returns 2.0
97+
```
98+
99+
The function has the following additional parameters:
100+
101+
- **offset**: starting index for `x`.
102+
103+
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 calculate the median value for every other element in `x` starting from the second element
104+
105+
```javascript
106+
var Float32Array = require( '@stdlib/array/float32' );
107+
108+
var x = new Float32Array( [ 2.0, 1.0, 2.0, 2.0, -2.0, 2.0, 3.0, 4.0 ] );
109+
110+
var v = smediansorted.ndarray( 4, x, 2, 1 );
111+
// returns 2.0
112+
```
113+
114+
</section>
115+
116+
<!-- /.usage -->
117+
118+
<section class="notes">
119+
120+
## Notes
121+
122+
- If `N <= 0`, both functions return `NaN`.
123+
- The input strided array must be sorted in either **strictly** ascending or descending order.
124+
125+
</section>
126+
127+
<!-- /.notes -->
128+
129+
<section class="examples">
130+
131+
## Examples
132+
133+
<!-- eslint no-undef: "error" -->
134+
135+
```javascript
136+
var linspace = require( '@stdlib/array/linspace' );
137+
var smediansorted = require( '@stdlib/stats/strided/smediansorted' );
138+
139+
var options = {
140+
'dtype': 'float32'
141+
};
142+
var x = linspace( -5.0, 5.0, 10, options );
143+
console.log( x );
144+
145+
var v = smediansorted( x.length, x, 1 );
146+
console.log( v );
147+
```
148+
149+
</section>
150+
151+
<!-- /.examples -->
152+
153+
<!-- C interface documentation. -->
154+
155+
* * *
156+
157+
<section class="c">
158+
159+
## C APIs
160+
161+
<!-- Section to include introductory text. Make sure to keep an empty line after the intro `section` element and another before the `/section` close. -->
162+
163+
<section class="intro">
164+
165+
</section>
166+
167+
<!-- /.intro -->
168+
169+
<!-- C usage documentation. -->
170+
171+
<section class="usage">
172+
173+
### Usage
174+
175+
```c
176+
#include "stdlib/stats/strided/smediansorted.h"
177+
```
178+
179+
#### stdlib_strided_smediansorted( N, \*X, strideX )
180+
181+
Computes the median value of a sorted single-precision floating-point strided array.
182+
183+
```c
184+
const float x[] = { 1.0f, 2.0f, 3.0f };
185+
186+
float v = stdlib_strided_smediansorted( 3, x, 1 );
187+
// returns 2.0f
188+
```
189+
190+
The function accepts the following arguments:
191+
192+
- **N**: `[in] CBLAS_INT` number of indexed elements.
193+
- **X**: `[in] float*` input array.
194+
- **strideX**: `[in] CBLAS_INT` stride length for `X`.
195+
196+
```c
197+
float stdlib_strided_smediansorted( const CBLAS_INT N, const float *X, const CBLAS_INT strideX );
198+
```
199+
200+
#### stdlib_strided_smediansorted_ndarray( N, \*X, strideX, offsetX )
201+
202+
Computes the median value of a sorted single-precision floating-point strided array using alternative indexing semantics.
203+
204+
```c
205+
const float x[] = { 1.0f, 2.0f, 3.0f };
206+
207+
float v = stdlib_strided_smediansorted_ndarray( 3, x, 1, 0 );
208+
// returns 2.0f
209+
```
210+
211+
The function accepts the following arguments:
212+
213+
- **N**: `[in] CBLAS_INT` number of indexed elements.
214+
- **X**: `[in] float*` input array.
215+
- **strideX**: `[in] CBLAS_INT` stride length for `X`.
216+
- **offsetX**: `[in] CBLAS_INT` starting index for `X`.
217+
218+
```c
219+
float stdlib_strided_smediansorted_ndarray( const CBLAS_INT N, const float *X, const CBLAS_INT strideX, const CBLAS_INT offsetX );
220+
```
221+
222+
</section>
223+
224+
<!-- /.usage -->
225+
226+
<!-- C API usage notes. Make sure to keep an empty line after the `section` element and another before the `/section` close. -->
227+
228+
<section class="notes">
229+
230+
</section>
231+
232+
<!-- /.notes -->
233+
234+
<!-- C API usage examples. -->
235+
236+
<section class="examples">
237+
238+
### Examples
239+
240+
```c
241+
#include "stdlib/stats/strided/smediansorted.h"
242+
#include <stdio.h>
243+
244+
int main( void ) {
245+
// Create a strided array:
246+
const float x[] = { 1.0f, 2.0f, 3.0f, 4.0f, 5.0f, 6.0f, 7.0f, 8.0f };
247+
248+
// Specify the number of elements:
249+
const int N = 4;
250+
251+
// Specify the stride length:
252+
const int strideX = 2;
253+
254+
// Compute the median value:
255+
float v = stdlib_strided_smediansorted( N, x, strideX );
256+
257+
// Print the result:
258+
printf( "median: %f\n", v );
259+
}
260+
```
261+
262+
</section>
263+
264+
<!-- /.examples -->
265+
266+
</section>
267+
268+
<!-- /.c -->
269+
270+
<!-- Section for related `stdlib` packages. Do not manually edit this section, as it is automatically populated. -->
271+
272+
<section class="related">
273+
274+
* * *
275+
276+
## See Also
277+
278+
- <span class="package-name">[`@stdlib/stats/strided/dmediansorted`][@stdlib/stats/strided/dmediansorted]</span><span class="delimiter">: </span><span class="description">calculate the median value of a sorted double-precision floating-point strided array.</span>
279+
- <span class="package-name">[`@stdlib/stats/base/mediansorted`][@stdlib/stats/base/mediansorted]</span><span class="delimiter">: </span><span class="description">calculate the median value of a sorted strided array.</span>
280+
- <span class="package-name">[`@stdlib/stats/base/smean`][@stdlib/stats/base/smean]</span><span class="delimiter">: </span><span class="description">calculate the arithmetic mean of a single-precision floating-point strided array.</span>
281+
282+
</section>
283+
284+
<!-- /.related -->
285+
286+
<!-- Section for all links. Make sure to keep an empty line after the `section` element and another before the `/section` close. -->
287+
288+
<section class="links">
289+
290+
[@stdlib/array/float32]: https://github.com/stdlib-js/stdlib/tree/develop/lib/node_modules/%40stdlib/array/float32
291+
292+
[mdn-typed-array]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray
293+
294+
<!-- <related-links> -->
295+
296+
[@stdlib/stats/strided/dmediansorted]: https://github.com/stdlib-js/stdlib/tree/develop/lib/node_modules/%40stdlib/stats/strided/dmediansorted
297+
298+
[@stdlib/stats/base/mediansorted]: https://github.com/stdlib-js/stdlib/tree/develop/lib/node_modules/%40stdlib/stats/base/mediansorted
299+
300+
[@stdlib/stats/base/smean]: https://github.com/stdlib-js/stdlib/tree/develop/lib/node_modules/%40stdlib/stats/base/smean
301+
302+
<!-- </related-links> -->
303+
304+
</section>
305+
306+
<!-- /.links -->

0 commit comments

Comments
 (0)