cidentity
Evaluate the identity function of a double-precision complex floating-point number.
The identity-function is defined as
for all z
.
Usage
var cidentity = require( '@stdlib/math/base/special/cidentity' );
cidentity( z )
Evaluates the identity function for a double-precision complex floating-point number.
var Complex128 = require( '@stdlib/complex/float64/ctor' );
var real = require( '@stdlib/complex/float64/real' );
var imag = require( '@stdlib/complex/float64/imag' );
var v = cidentity( new Complex128( -1.0, 2.0 ) );
// returns <Complex128>
var re = real( v );
// returns -1.0
var im = imag( v );
// returns 2.0
Examples
var discreteUniform = require( '@stdlib/random/base/discrete-uniform' );
var Complex128 = require( '@stdlib/complex/float64/ctor' );
var cidentity = require( '@stdlib/math/base/special/cidentity' );
var z;
var i;
for ( i = 0; i < 100; i++ ) {
z = new Complex128( discreteUniform( -50, 50 ), discreteUniform( -50, 50 ) );
console.log( 'identity(%s) = %s', z, cidentity( z ) );
}
C APIs
Usage
#include "stdlib/math/base/special/cidentity.h"
stdlib_base_cidentity( z )
Evaluates the identity function for a double-precision complex floating-point number.
#include "stdlib/complex/float64/ctor.h"
#include "stdlib/complex/float64/real.h"
#include "stdlib/complex/float64/imag.h"
stdlib_complex128_t z = stdlib_complex128( 2.5, -1.5 );
stdlib_complex128_t out = stdlib_base_cidentity( z );
double re = stdlib_complex128_real( out );
// returns 2.5
double im = stdlib_complex128_imag( out );
// returns -1.5
The function accepts the following arguments:
- z:
[in] stdlib_complex128_t
input value.
stdlib_complex128_t stdlib_base_cidentity( const stdlib_complex128_t z );
Examples
#include "stdlib/math/base/special/cidentity.h"
#include "stdlib/complex/float64/ctor.h"
#include "stdlib/complex/float64/reim.h"
#include <stdio.h>
int main() {
const stdlib_complex128_t x[] = {
stdlib_complex128( 3.14, 1.5 ),
stdlib_complex128( -3.14, -1.5 ),
stdlib_complex128( 0.0, 0.0 ),
stdlib_complex128( 0.0/0.0, 0.0/0.0 )
};
stdlib_complex128_t v;
stdlib_complex128_t y;
double re1;
double im1;
double re2;
double im2;
int i;
for ( i = 0; i < 4; i++ ) {
v = x[ i ];
y = stdlib_base_cidentity( v );
stdlib_complex128_reim( v, &re1, &im1 );
stdlib_complex128_reim( y, &re2, &im2 );
printf( "cidentity(%lf + %lfi) = %lf + %lfi\n", re1, im1, re2, im2 );
}
}