feat: add math/base/special/sind

lib/node_modules/@stdlib/math/base/special/sind/README.md

@@ -0,0 +1,109 @@
+<!--
+
+@license Apache-2.0
+
+Copyright (c) 2018 The Stdlib Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+   http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+
+-->
+
+# Sine
+
+> Compute the [sine][sine] of a number.
+
+<section class="usage">
+
+## Usage
+
+```javascript
+var sin = require( '@stdlib/math/base/special/sin' );
+```
+
+#### sin( x )
+
+Computes the [sine][sine] of a `number` (in radians).
+
+```javascript
+var v = sin( 0.0 );
+// returns ~0.0
+
+v = sin( 3.141592653589793/2.0 );
+// returns ~1.0
+
+v = sin( -3.141592653589793/6.0 );
+// returns ~-0.5
+```
+
+</section>
+
+<!-- /.usage -->
+
+<section class="examples">
+
+## Examples
+
+<!-- eslint no-undef: "error" -->
+
+```javascript
+var linspace = require( '@stdlib/array/base/linspace' );
+var TWO_PI = require( '@stdlib/constants/float64/two-pi' );
+var sin = require( '@stdlib/math/base/special/sin' );
+
+var x = linspace( 0.0, TWO_PI, 100 );
+
+var i;
+for ( i = 0; i < x.length; i++ ) {
+    console.log( sin( x[ i ] ) );
+}
+```
+
+</section>
+
+<!-- /.examples -->
+
+<!-- Section for related `stdlib` packages. Do not manually edit this section, as it is automatically populated. -->
+
+<section class="related">
+
+* * *
+
+## See Also
+
+-   <span class="package-name">[`@stdlib/math/base/special/cos`][@stdlib/math/base/special/cos]</span><span class="delimiter">: </span><span class="description">compute the cosine of a number.</span>
+-   <span class="package-name">[`@stdlib/math/base/special/sinpi`][@stdlib/math/base/special/sinpi]</span><span class="delimiter">: </span><span class="description">compute sin(πx).</span>
+-   <span class="package-name">[`@stdlib/math/base/special/tan`][@stdlib/math/base/special/tan]</span><span class="delimiter">: </span><span class="description">evaluate the tangent of a number.</span>
+
+</section>
+
+<!-- /.related -->
+
+<!-- Section for all links. Make sure to keep an empty line after the `section` element and another before the `/section` close. -->
+
+<section class="links">
+
+[sine]: https://en.wikipedia.org/wiki/Sine
+
+<!-- <related-links> -->
+
+[@stdlib/math/base/special/cos]: https://github.com/stdlib-js/stdlib/tree/develop/lib/node_modules/%40stdlib/math/base/special/cos
+
+[@stdlib/math/base/special/sinpi]: https://github.com/stdlib-js/stdlib/tree/develop/lib/node_modules/%40stdlib/math/base/special/sinpi
+
+[@stdlib/math/base/special/tan]: https://github.com/stdlib-js/stdlib/tree/develop/lib/node_modules/%40stdlib/math/base/special/tan
+
+<!-- </related-links> -->
+
+</section>
+
+<!-- /.links -->

lib/node_modules/@stdlib/math/base/special/sind/docs/repl.txt

@@ -0,0 +1,28 @@
+
+{{alias}}( x )
+    Computes the sine of a number.
+
+    Parameters
+    ----------
+    x: number
+        Input value (in degrees).
+
+    Returns
+    -------
+    y: number
+        Sine.
+
+    Examples
+    --------
+    > var y = {{alias}}( 0.0 )
+    ~0.0
+    > y = {{alias}}( 90 )
+    ~1.0
+    > y = {{alias}}( -30 )
+    ~-0.5
+    > y = {{alias}}( NaN )
+    NaN
+
+    See Also
+    --------
+

lib/node_modules/@stdlib/math/base/special/sind/docs/types/index.d.ts

@@ -0,0 +1,48 @@
+/*
+* @license Apache-2.0
+*
+* Copyright (c) 2019 The Stdlib Authors.
+*
+* Licensed under the Apache License, Version 2.0 (the "License");
+* you may not use this file except in compliance with the License.
+* You may obtain a copy of the License at
+*
+*    http://www.apache.org/licenses/LICENSE-2.0
+*
+* Unless required by applicable law or agreed to in writing, software
+* distributed under the License is distributed on an "AS IS" BASIS,
+* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+* See the License for the specific language governing permissions and
+* limitations under the License.
+*/
+
+// TypeScript Version: 2.0
+
+/**
+* Computes the sine of a number.
+*
+* @param x - input value (in degrees)
+* @returns sine
+*
+* @example
+* var v = sind( 0.0 );
+* // returns ~0.0
+*
+* @example
+* var v = sind( 90 );
+* // returns ~1.0
+*
+* @example
+* var v = sind( -30 );
+* // returns ~-0.5
+*
+* @example
+* var v = sind( NaN );
+* // returns NaN
+*/
+declare function sind( x: number ): number;
+
+
+// EXPORTS //
+
+export = sind;

lib/node_modules/@stdlib/math/base/special/sind/docs/types/test.ts

@@ -0,0 +1,44 @@
+/*
+* @license Apache-2.0
+*
+* Copyright (c) 2019 The Stdlib Authors.
+*
+* Licensed under the Apache License, Version 2.0 (the "License");
+* you may not use this file except in compliance with the License.
+* You may obtain a copy of the License at
+*
+*    http://www.apache.org/licenses/LICENSE-2.0
+*
+* Unless required by applicable law or agreed to in writing, software
+* distributed under the License is distributed on an "AS IS" BASIS,
+* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+* See the License for the specific language governing permissions and
+* limitations under the License.
+*/
+
+import sind = require( './index' );
+
+
+// TESTS //
+
+// The function returns a number...
+{
+	sind( 8 ); // $ExpectType number
+}
+
+// The function does not compile if provided a value other than a number...
+{
+	sind( true ); // $ExpectError
+	sind( false ); // $ExpectError
+	sind( null ); // $ExpectError
+	sind( undefined ); // $ExpectError
+	sind( '5' ); // $ExpectError
+	sind( [] ); // $ExpectError
+	sind( {} ); // $ExpectError
+	sind( ( x: number ): number => x ); // $ExpectError
+}
+
+// The function does not compile if provided insufficient arguments...
+{
+	sind(); // $ExpectError
+}

lib/node_modules/@stdlib/math/base/special/sind/examples/index.js

@@ -0,0 +1,29 @@
+/**
+* @license Apache-2.0
+*
+* Copyright (c) 2018 The Stdlib Authors.
+*
+* Licensed under the Apache License, Version 2.0 (the "License");
+* you may not use this file except in compliance with the License.
+* You may obtain a copy of the License at
+*
+*    http://www.apache.org/licenses/LICENSE-2.0
+*
+* Unless required by applicable law or agreed to in writing, software
+* distributed under the License is distributed on an "AS IS" BASIS,
+* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+* See the License for the specific language governing permissions and
+* limitations under the License.
+*/
+
+'use strict';
+
+var linspace = require( '@stdlib/array/base/linspace' );
+var sind = require( './../lib' );
+
+var x = linspace( 0, 30, -90 );
+
+var i;
+for ( i = 0; i < x.length; i++ ) {
+	console.log( 'sind(%d) = %d', x[ i ], sind( x[ i ] ) );
+}

lib/node_modules/@stdlib/math/base/special/sind/lib/index.js

@@ -0,0 +1,49 @@
+/**
+* @license Apache-2.0
+*
+* Copyright (c) 2018 The Stdlib Authors.
+*
+* Licensed under the Apache License, Version 2.0 (the "License");
+* you may not use this file except in compliance with the License.
+* You may obtain a copy of the License at
+*
+*    http://www.apache.org/licenses/LICENSE-2.0
+*
+* Unless required by applicable law or agreed to in writing, software
+* distributed under the License is distributed on an "AS IS" BASIS,
+* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+* See the License for the specific language governing permissions and
+* limitations under the License.
+*/
+
+'use strict';
+
+/**
+* Compute the sine of a number.
+*
+* @module @stdlib/math/base/special/sind
+*
+* @example
+* var sind = require( '@stdlib/math/base/special/sind' );
+*
+* var v = sind( 0.0 );
+* // returns ~0.0
+*
+* v = sind( 90 );
+* // returns ~1.0
+*
+* v = sind( -30 );
+* // returns ~-0.5
+*
+* v = sind( NaN );
+* // returns NaN
+*/
+
+// MODULES //
+
+var sind = require( './sind.js' );
+
+
+// EXPORTS //
+
+module.exports = sind;

lib/node_modules/@stdlib/math/base/special/sind/lib/sind.js

@@ -0,0 +1,86 @@
+/**
+* @license Apache-2.0
+*
+* Copyright (c) 2018 The Stdlib Authors.
+*
+* Licensed under the Apache License, Version 2.0 (the "License");
+* you may not use this file except in compliance with the License.
+* You may obtain a copy of the License at
+*
+*    http://www.apache.org/licenses/LICENSE-2.0
+*
+* Unless required by applicable law or agreed to in writing, software
+* distributed under the License is distributed on an "AS IS" BASIS,
+* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+* See the License for the specific language governing permissions and
+* limitations under the License.
+*/
+
+'use strict';
+
+// MODULES //
+
+var isnan = require('@stdlib/math/base/assert/is-nan');
+var isinfinite = require('@stdlib/math/base/assert/is-infinite');
+var abs = require('@stdlib/math/base/special/abs');
+var kernelSin = require('@stdlib/math/base/special/kernel-sin');
+var kernelCos = require('@stdlib/math/base/special/kernel-cos');
+var PI = require('@stdlib/constants/float64/pi');
+
+/**
+* Compute the sine of a number.
+*
+* @module @stdlib/math/base/special/sind
+*
+* @example
+* var sind = require( '@stdlib/math/base/special/sind' );
+*
+* var v = sind( 0.0 );
+* // returns ~0.0
+*
+* v = sind( 90 );
+* // returns ~1.0
+*
+* v = sind( -30 );
+* // returns ~-0.5
+*
+* v = sind( NaN );
+* // returns NaN
+*/
+
+function deg2rad(x) {
+	return (x * PI) / 180;
+}
+
+function sind(x) {
+	if (isinfinite(x)) {
+		return NaN;
+	}
+	if (isnan(x)) {
+		return NaN;
+	}
+	var rad;
+	x = ((x % 360) + 360) % 360
+	if (x <= 45) {
+		rad = deg2rad(x);
+		return kernelSin(rad, 0);
+	}
+	if (x <= 135) {
+		rad = deg2rad(x - 90);
+		return kernelCos(rad, 0);
+	}
+	if (x <= 225) {
+		rad = deg2rad(180 - x);
+		return kernelSin(rad, 0);
+	}
+	if (x <= 315) {
+		rad = deg2rad(x - 270);
+		return -kernelCos(rad, 0);
+	}
+	rad = deg2rad(360 - x)
+	return -kernelSin(rad, 0);
+}
+
+// EXPORTS //
+
+module.exports = sind;