# Ceil > Round a complex number toward positive infinity.
## Usage ```javascript var cceil = require( '@stdlib/math/base/special/cceil' ); ``` #### cceil( \[out,] re, im ) Rounds a `complex` number comprised of a **real** component `re` and an **imaginary** component `im` toward positive infinity. ```javascript var v = cceil( -4.2, 5.5 ); // returns [ -4.0, 6.0 ] v = cceil( 9.99999, 0.1 ); // returns [ 10.0, 1.0 ] v = cceil( 0.0, 0.0 ); // returns [ 0.0, 0.0 ] v = cceil( NaN, NaN ); // returns [ NaN, NaN ] ``` By default, the function returns real and imaginary components as a two-element `array`. To avoid unnecessary memory allocation, the function supports providing an output (destination) object. ```javascript var Float32Array = require( '@stdlib/array/float32' ); var out = new Float32Array( 2 ); var v = cceil( out, -4.2, 5.5 ); // returns [ -4.0, 6.0 ] var bool = ( v === out ); // returns true ```
## Examples ```javascript var Complex128 = require( '@stdlib/complex/float64' ); var randu = require( '@stdlib/random/base/randu' ); var real = require( '@stdlib/complex/real' ); var imag = require( '@stdlib/complex/imag' ); var cceil = require( '@stdlib/math/base/special/cceil' ); var re; var im; var z; var o; var w; var i; for ( i = 0; i < 100; i++ ) { re = ( randu()*100.0 ) - 50.0; im = ( randu()*100.0 ) - 50.0; z = new Complex128( re, im ); o = cceil( real(z), imag(z) ); w = new Complex128( o[ 0 ], o[ 1 ] ); console.log( 'ceil(%s) = %s', z.toString(), w.toString() ); } ```