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Return a double-precision floating-point number with the magnitude of
xand the sign ofy.
To use in Observable,
copysign = require( 'https://cdn.jsdelivr.net/gh/stdlib-js/math-base-special-copysign@umd/browser.js' )To vendor stdlib functionality and avoid installing dependency trees for Node.js, you can use the UMD server build:
var copysign = require( 'path/to/vendor/umd/math-base-special-copysign/index.js' )To include the bundle in a webpage,
<script type="text/javascript" src="https://cdn.jsdelivr.net/gh/stdlib-js/math-base-special-copysign@umd/browser.js"></script>If no recognized module system is present, access bundle contents via the global scope:
<script type="text/javascript">
(function () {
window.copysign;
})();
</script>Returns a double-precision floating-point number with the magnitude of x and the sign of y.
var z = copysign( -3.14, 10.0 );
// returns 3.14
z = copysign( 3.14, -1.0 );
// returns -3.14
z = copysign( 1.0, -0.0 );
// returns -1.0
z = copysign( -3.14, -0.0 );
// returns -3.14
z = copysign( -0.0, 1.0 );
// returns 0.0- According to the IEEE754 standard, a
NaNhas a biased exponent equal to2047, a significand greater than0, and a sign bit equal to either1or0. In which case,NaNmay not correspond to just one but many binary representations. Accordingly, care should be taken to ensure thatyis notNaN; otherwise, behavior may be indeterminate.
<!DOCTYPE html>
<html lang="en">
<body>
<script type="text/javascript" src="https://cdn.jsdelivr.net/gh/stdlib-js/random-array-uniform@umd/browser.js"></script>
<script type="text/javascript" src="https://cdn.jsdelivr.net/gh/stdlib-js/console-log-each-map@umd/browser.js"></script>
<script type="text/javascript" src="https://cdn.jsdelivr.net/gh/stdlib-js/math-base-special-copysign@umd/browser.js"></script>
<script type="text/javascript">
(function () {
var opts = {
'dtype': 'float64'
};
var x = uniform( 100, -50.0, 50.0, opts );
var y = uniform( 100, -5.0, 5.0, opts );
// Generate random double-precision floating-point numbers `x` and `y` and copy the sign of `y` to `x`...
logEachMap( 'x: %0.4f, y: %0.4f => %0.4f', x, y, copysign );
})();
</script>
</body>
</html>@stdlib/math-base/special/flipsign: return a double-precision floating-point number with the magnitude of x and the sign of x*y.
This package is part of stdlib, a standard library for JavaScript and Node.js, with an emphasis on numerical and scientific computing. The library provides a collection of robust, high performance libraries for mathematics, statistics, streams, utilities, and more.
For more information on the project, filing bug reports and feature requests, and guidance on how to develop stdlib, see the main project repository.
See LICENSE.
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