function gcusum( arrays ) {
	var x = arrays[ 0 ];
	var y = arrays[ 1 ];
	var s = arrays[ 2 ];
	var v = getData( s )[ getOffset( s ) ];
	strided( numelDimension( x, 0 ), v, getData( x ), getStride( x, 0 ), getOffset( x ), getData( y ), getStride( y, 0 ), getOffset( y ) ); // eslint-disable-line max-len
	return y;
}
Computes the cumulative sum of a one-dimensional ndarray.

@param {ArrayLikeObject<Object>} arrays - array-like object containing an input ndarray, an output ndarray, and an ndarray containing the initial sum
@returns {number} sum

@example
var ndarray2array = require( '@stdlib/ndarray/to-array' );
var ndarray = require( '@stdlib/ndarray/base/ctor' );
var scalar2ndarray = require( '@stdlib/ndarray/base/from-scalar' );

var xbuf = [ 1.0, 3.0, 4.0, 2.0 ];
var x = new ndarray( 'generic', xbuf, [ 4 ], [ 1 ], 0, 'row-major' );

var ybuf = [ 0.0, 0.0, 0.0, 0.0 ];
var y = new ndarray( 'generic', xbuf, [ 4 ], [ 1 ], 0, 'row-major' );

var initial = scalar2ndarray( 0.0, 'generic', 'row-major' );

var v = gcusum( [ x, y, initial ] );
// returns <ndarray>

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

var arr = ndarray2array( v );
// returns [ 1.0, 4.0, 8.0, 10.0 ]