cunoneBy

Cumulatively test whether every array element in a provided array fails a test implemented by a predicate function.

Usage

var cunoneBy = require( '@stdlib/array/base/cunone-by' );

cunoneBy( x, predicate[, thisArg ] )

Cumulatively tests whether every array element in a provided array fails a test implemented by a predicate function.

function fcn( value) {
    return ( value > 0 );
}

var x = [ 0, 0, 0, 1, 0 ];

var y = cunoneBy( x, fcn );
// returns [ true, true, true, false, false ]

The invoked predicate function is provided three arguments:

  • value: collection element.
  • index: collection index.
  • collection: input collection.

To set the function execution context, provide a thisArg.

function fcn( v ) {
    this.count += 1;
    return ( v > 0 );
}

var x = [ 0, 0, 1, 0, 0 ];

var context = {
    'count': 0
};

var bool = cunoneBy( x, fcn, context );
// returns [ true, true, false, false, false ]

var count = context.count;
// returns 3

cunoneBy.assign( x, out, stride, offset, predicate[, thisArg ] )

Cumulatively tests whether every array element in a provided array fails a test implemented by a predicate function and assigns the values to elements in a provided output array.

function fcn( v ) {
    return ( v > 0 );
}

var x = [ 0, 0, 0, 1, 0 ];
var y = [ false, null, false, null, false, null, false, null, false, null ];

var out = cunoneBy.assign( x, y, 2, 0, fcn );
// returns [ true, null, true, null, true, null, false, null, false, null ]

var bool = ( out === y );
// returns true

Examples

var bernoulli = require( '@stdlib/random/array/bernoulli' );
var cunoneBy = require( '@stdlib/array/base/cunone-by' );

function fcn( value ) {
    return ( value > 0 );
}

// Create an array of random values:
var x = bernoulli( 10, 0.1 );
console.log( x );

// Cumulatively tests whether every array element fails a test:
var y = cunoneBy( x, fcn );
console.log( y );
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