Compute sqrt(1 + x) - 1.
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> Compute sqrt( 1 + x ) - 1.
``bash`
npm install @stdlib/math-base-special-sqrt1pm1
`javascript`
var sqrt1pm1 = require( '@stdlib/math-base-special-sqrt1pm1' );
#### sqrt1pm1( x )
Computes sqrt( 1 + x ) - 1 more accurately for small x.
`javascript
var v = sqrt1pm1( 3.0 );
// returns 1.0
v = sqrt1pm1( 0.5 );
// returns ~0.225
v = sqrt1pm1( 0.02 );
// returns ~0.01
v = sqrt1pm1( -0.5 );
// returns ~-0.293
v = sqrt1pm1( -1.1 );
// returns NaN
v = sqrt1pm1( NaN );
// returns NaN
`
`javascript
var discreteUniform = require( '@stdlib/random-array-discrete-uniform' );
var logEachMap = require( '@stdlib/console-log-each-map' );
var sqrt1pm1 = require( '@stdlib/math-base-special-sqrt1pm1' );
var opts = {
'dtype': 'float64'
};
var x = discreteUniform( 100, 0, 100, opts );
logEachMap( 'sqrt(1+%d) - 1 = %0.4f', x, sqrt1pm1 );
`
*
`c`
#include "stdlib/math/base/special/sqrt1pm1.h"
#### stdlib_base_sqrt1pm1( x )
Computes sqrt( 1 + x ) - 1 more accurately for small x.
`c
double out = stdlib_base_sqrt1pm1( 3.0 );
// returns 1.0
out = stdlib_base_sqrt1pm1( 0.5 );
// returns ~0.225
`
The function accepts the following arguments:
- x: [in] double input value.
`c`
double stdlib_base_sqrt1pm1( const double x );
`c
#include "stdlib/math/base/special/sqrt1pm1.h"
#include
#include
int main( void ) {
double x;
double v;
int i;
for ( i = 0; i < 100; i++ ) {
x = ( (double)rand() / (double)RAND_MAX ) * 100.0;
v = stdlib_base_sqrt1pm1( x );
printf( "sqrt(1+%lf) - 1 = %lf\n", x, v );
}
}
`
*
- [@stdlib/math-base/special/sqrt][@stdlib/math/base/special/sqrt]: compute the principal square root of a double-precision floating-point number.
*
This package is part of [stdlib][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][stdlib], see the main project [repository][stdlib].
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