@stdlib/math-base-special-atan2
v0.3.0
Published
Compute the angle in the plane (in radians) between the positive x-axis and the ray from (0,0) to the point (x,y).
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atan2
Compute the angle in the plane (in radians) between the positive x-axis and the ray from
(0,0)
to the point(x,y)
.
Installation
npm install @stdlib/math-base-special-atan2
Usage
var atan2 = require( '@stdlib/math-base-special-atan2' );
atan2( y, x )
Computes the angle in the plane (in radians) between the positive x-axis and the ray from (0,0)
to the point (x,y)
.
var v = atan2( 2.0, 2.0 ); // => atan(1.0)
// returns ~0.785
v = atan2( 6.0, 2.0 ); // => atan(3.0)
// returns ~1.249
v = atan2( -1.0, -1.0 ); // => atan(1.0) - π
// returns ~-2.356
v = atan2( 3.0, 0.0 ); // => π/2
// returns ~1.571
v = atan2( -2.0, 0.0 ); // => -π/2
// returns ~-1.571
v = atan2( 0.0, 0.0 );
// returns 0.0
v = atan2( 3.0, NaN );
// returns NaN
Examples
var randu = require( '@stdlib/random-base-randu' );
var atan2 = require( '@stdlib/math-base-special-atan2' );
var y;
var x;
var i;
for ( i = 0; i < 100; i++ ) {
y = randu() * 100.0;
x = randu() * 100.0;
console.log( 'y: %d, \t x: %d, \t atan2(y,x): %d', y.toFixed( 4 ), x.toFixed( 4 ), atan2( y, x ).toFixed( 4 ) );
}
C APIs
Usage
#include "stdlib/math/base/special/atan2.h"
stdlib_base_atan2( y, x )
Computes the angle in the plane (in radians) between the positive x-axis and the ray from (0,0)
to the point (x,y)
.
double out = stdlib_base_atan2( 2.0, 2.0 );
// returns ~0.785
out = stdlib_base_atan2( 6.0, 2.0 );
// returns ~1.249
The function accepts the following arguments:
- y:
[in] double
-y
coordinate - x:
[in] double
-x
coordinate
double stdlib_base_atan2( const double y, const double x );
Examples
#include "stdlib/math/base/special/atan2.h"
#include <stdlib.h>
#include <stdio.h>
int main( void ) {
double y;
double x;
double v;
int i;
for ( i = 0; i < 100; i++ ) {
y = ( ( (double)rand() / (double)RAND_MAX ) * 100.0 );
x = ( ( (double)rand() / (double)RAND_MAX ) * 100.0 );
v = stdlib_base_atan2( y, x );
printf( "atan2(%lf, %lf) = %lf\n", y, x, v );
}
return 0;
}
See Also
@stdlib/math-base/special/atan
: compute the arctangent of a double-precision floating-point number.
Notice
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.
Community
Copyright
Copyright © 2016-2024. The Stdlib Authors.