atanh

Compute the hyperbolic arctangent of a double-precision floating-point number.

Usage

var atanh = require( '@stdlib/math/base/special/atanh' );

atanh( x )

Computes the hyperbolic arctangent of a double-precision floating-point number.

var v = atanh( 0.0 );
// returns 0.0

v = atanh( -0.0 );
// returns -0.0

v = atanh( 0.5 );
// returns ~0.549

v = atanh( 0.9 );
// returns ~1.472

v = atanh( 1.0 );
// returns Infinity

v = atanh( -1.0 );
// returns -Infinity

The domain of x is restricted to [-1,1]. If |x| > 1, the function returns NaN.

var v = atanh( -3.14 );
// returns NaN

Examples

var uniform = require( '@stdlib/random/array/uniform' );
var logEachMap = require( '@stdlib/console/log-each-map' );
var atanh = require( '@stdlib/math/base/special/atanh' );

var x = uniform( 100, -1.0, 1.0, {
    'dtype': 'float64'
});

logEachMap( 'atanh(%0.4f) = %0.4f', x, atanh );

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C APIs

Usage

#include "stdlib/math/base/special/atanh.h"

stdlib_base_atanh( x )

Computes the hyperbolic arctangent of double-precision floating-point number.

double out = stdlib_base_atanh( 0.0 );
// returns 0.0

out = stdlib_base_atanh( -0.0 );
// returns -0.0

The function accepts the following arguments:

• x: [in] double input value.

double stdlib_base_atanh( const double x );

Examples

#include "stdlib/math/base/special/atanh.h"
#include <stdio.h>

int main( void ) {
    const double x[] = { -1.0, -0.78, -0.56, -0.33, -0.11, 0.11, 0.33, 0.56, 0.78, 1.0 };

    double v;
    int i;
    for ( i = 0; i < 10; i++ ) {
        v = stdlib_base_atanh( x[ i ] );
        printf( "atanh(%lf) = %lf\n", x[ i ], v );
    }
}

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See Also

• @stdlib/math/base/special/acosh: compute the hyperbolic arccosine of a double-precision floating-point number.
• @stdlib/math/base/special/asinh: compute the hyperbolic arcsine of a double-precision floating-point number.
• @stdlib/math/base/special/atan: compute the arctangent of a double-precision floating-point number.