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Add functional if-then utility
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‎lib/node_modules/@stdlib/utils/if-then/README.md‎

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# ifthen
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> If a condition is truthy, invoke `x`; otherwise, invoke `y`.
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<!-- Section to include introductory text. Make sure to keep an empty line after the intro `section` element and another before the `/section` close. -->
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<section class="intro">
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</section>
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<!-- /.intro -->
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<!-- Package usage documentation. -->
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<section class="usage">
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## Usage
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``` javascript
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var ifthen = require( '@stdlib/utils/if-then' );
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```
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#### ifthen( bool, x, y )
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If a condition is truthy, invokes `x`; otherwise, invokes `y`.
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``` javascript
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function x() {
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return 1.0;
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}
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function y() {
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return -1.0;
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}
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var z = ifthen( true, x, y );
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// returns 1.0
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z = ifthen( false, x, y );
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// returns -1.0
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```
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</section>
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<!-- /.usage -->
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<!-- Package usage notes. Make sure to keep an empty line after the `section` element and another before the `/section` close. -->
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<section class="notes">
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## Notes
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* The function is similar to [`ifelse()`][@stdlib/utils/if-else], but allows deferred argument evaluation.
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</section>
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<!-- /.notes -->
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<!-- Package usage examples. -->
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<section class="examples">
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## Examples
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``` javascript
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var randu = require( '@stdlib/math/base/random/randu' );
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var ifthen = require( '@stdlib/utils/if-then' );
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var z;
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var i;
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function x() {
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return repeatString( 'BOOP', ceil( randu()*3.0 ) );
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}
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function y() {
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return repeatString( 'beep', ceil( randu()*5.0 ) );
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}
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for ( i = 0; i < 100; i++ ) {
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z = ifthen( randu() > 0.9, x, y );
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console.log( z );
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}
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```
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</section>
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<!-- /.examples -->
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<!-- Section to include cited references. If references are included, add a horizontal rule *before* the section. Make sure to keep an empty line after the `section` element and another before the `/section` close. -->
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<section class="references">
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</section>
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<!-- /.references -->
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<!-- Section for all links. Make sure to keep an empty line after the `section` element and another before the `/section` close. -->
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<section class="links">
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[@stdlib/utils/if-else]: https://github.com/stdlib-js/stdlib
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</section>
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<!-- /.links -->

‎lib/node_modules/@stdlib/utils/if-then/benchmark/benchmark.js‎

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'use strict';
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// MODULES //
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var bench = require( '@stdlib/bench' );
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var randu = require( '@stdlib/math/base/random/randu' );
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var isnan = require( '@stdlib/math/base/assert/is-nan' );
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var pkg = require( './../package.json' ).name;
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var ifthen = require( './../lib' );
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// MAIN //
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bench( pkg, function benchmark( b ) {
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var z;
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var i;
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function x() {
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return randu() * 100.0;
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}
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function y() {
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return -1.0 * randu() * 100.0;
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}
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b.tic();
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for ( i = 0; i < b.iterations; i++ ) {
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z = ifthen( randu() > 0.5, x, y );
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if ( isnan( z ) ) {
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b.fail( 'should not return NaN' );
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}
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}
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b.toc();
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if ( isnan( z ) ) {
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b.fail( 'should not return NaN' );
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}
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b.pass( 'benchmark finished' );
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b.end();
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});

‎lib/node_modules/@stdlib/utils/if-then/docs/repl.txt‎

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{{alias}}( bool, x, y )
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If a condition is truthy, invoke `x`; otherwise, invoke `y`.
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Parameters
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----------
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bool: boolean
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Condition.
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x: Function
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Function to invoke if a condition is truthy.
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y: Function
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Function to invoke if a condition is falsy.
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Returns
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-------
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z: any
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Return value of either `x` or `y`.
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Examples
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--------
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> function x() { return 'yes'; };
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> function y() { return 'no'; };
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> var z = {{alias}}( true, x, y )
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'yes'
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> z = {{alias}}( false, x, y )
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'no'
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See Also
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--------
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‎lib/node_modules/@stdlib/utils/if-then/examples/index.js‎

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'use strict';
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var randu = require( '@stdlib/math/base/random/randu' );
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var ceil = require( '@stdlib/math/base/special/ceil' );
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var repeatString = require( '@stdlib/string/repeat' );
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var ifthen = require( './../lib' );
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var z;
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var i;
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function x() {
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return repeatString( 'BOOP', ceil( randu()*3.0 ) );
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}
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function y() {
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return repeatString( 'beep', ceil( randu()*5.0 ) );
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}
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for ( i = 0; i < 100; i++ ) {
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z = ifthen( randu() > 0.9, x, y );
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console.log( z );
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}

‎lib/node_modules/@stdlib/utils/if-then/lib/if_then.js‎

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'use strict';
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// MODULES //
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var isFunction = require( '@stdlib/assert/is-function' );
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// MAIN //
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/**
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* If a condition is truthy, invokes `x`; otherwise, invokes `y`.
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*
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* @param {boolean} bool - condition
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* @param {Function} x - function to invoke if a condition is truthy
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* @param {Function} y - function to invoke if a condition is falsy
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* @throws {TypeError} second argument must be a function
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* @throws {TypeError} third argument must be a function
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* @returns {*} return value of either `x` or `y`
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*
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* @example
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* var randu = require( '@stdlib/math/base/random/randu' );
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*
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* function x() {
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* return randu() * 100.0;
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* }
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*
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* function y() {
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* return -1.0 * randu() * 100.0;
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* }
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*
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* var z = ifthen( randu() > 0.5, x, y );
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* // returns <number>
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*/
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function ifthen( bool, x, y ) {
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if ( !isFunction( x ) ) {
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throw new TypeError( 'invalid input argument. Second argument must be a function. Value: `'+x+'`.' );
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}
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if ( !isFunction( y ) ) {
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throw new TypeError( 'invalid input argument. Third argument must be a function. Value: `'+y+'`.' );
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}
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if ( bool ) {
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return x();
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}
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return y();
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} // end FUNCTION ifthen()
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// EXPORTS //
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module.exports = ifthen;

‎lib/node_modules/@stdlib/utils/if-then/lib/index.js‎

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'use strict';
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/**
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* If a condition is truthy, invoke `x`; otherwise, invoke `y`.
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*
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* @module @stdlib/utils/if-then
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*
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* @example
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* var randu = require( '@stdlib/math/base/random/randu' );
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* var ifthen = require( '@stdlib/utils/if-then' );
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*
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* function x() {
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* return randu() * 100.0;
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* }
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*
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* function y() {
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* return -1.0 * randu() * 100.0;
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* }
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*
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* var z = ifthen( randu() > 0.5, x, y );
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* // returns <number>
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*/
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// MODULES //
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var ifthen = require( './if_then.js' );
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// EXPORTS //
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module.exports = ifthen;

‎lib/node_modules/@stdlib/utils/if-then/package.json‎

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{
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"name": "@stdlib/utils/if-then",
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"version": "0.0.0",
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"description": "If a condition is truthy, invoke `x`; otherwise, invoke `y`.",
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"author": {
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"name": "The Stdlib Authors",
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"url": "https://github.com/stdlib-js/stdlib/graphs/contributors"
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},
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"contributors": [
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{
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"name": "The Stdlib Authors",
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"url": "https://github.com/stdlib-js/stdlib/graphs/contributors"
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}
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],
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"scripts": {},
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"main": "./lib",
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"repository": {
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"type": "git",
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"url": "git://github.com/stdlib-js/stdlib.git"
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},
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"homepage": "https://github.com/stdlib-js/stdlib",
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"keywords": [
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"stdlib",
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"stdutils",
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"stdutil",
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"utilities",
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"utility",
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"utils",
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"util",
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"if",
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"else",
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"then",
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"if-else",
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"if-then",
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"defer",
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"deferred",
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"delay",
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"delayed",
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"control",
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"flow",
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"condition",
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"conditional",
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"either-or"
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],
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"bugs": {
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"url": "https://github.com/stdlib-js/stdlib/issues"
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},
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"dependencies": {},
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"devDependencies": {},
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"engines": {
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"node": ">=0.10.0",
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"npm": ">2.7.0"
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},
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"license": "Apache-2.0"
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}

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