function binary0d( x, y, z, fcn ) {
	z.accessors[ 1 ]( z.data, z.offset, fcn( x.accessors[ 0 ]( x.data, x.offset ), y.accessors[ 0 ]( y.data, y.offset ) ) ); // eslint-disable-line max-len
}
Applies a binary callback to elements in zero-dimensional input ndarrays and assigns results to elements in an equivalently shaped output ndarray.

@private
@param {Object} x - object containing input ndarray meta data
@param {string} x.dtype - data type
@param {Collection} x.data - data buffer
@param {NonNegativeIntegerArray} x.shape - dimensions
@param {IntegerArray} x.strides - stride lengths
@param {NonNegativeInteger} x.offset - index offset
@param {string} x.order - specifies whether `x` is row-major (C-style) or column-major (Fortran-style)
@param {Array<Function>} x.accessors - data buffer accessors
@param {Object} y - object containing input ndarray meta data
@param {string} y.dtype - data type
@param {Collection} y.data - data buffer
@param {NonNegativeIntegerArray} y.shape - dimensions
@param {IntegerArray} y.strides - stride lengths
@param {NonNegativeInteger} y.offset - index offset
@param {string} y.order - specifies whether `y` is row-major (C-style) or column-major (Fortran-style)
@param {Array<Function>} y.accessors - data buffer accessors
@param {Object} z - object containing output ndarray meta data
@param {string} z.dtype - data type
@param {Collection} z.data - data buffer
@param {NonNegativeIntegerArray} z.shape - dimensions
@param {IntegerArray} z.strides - stride lengths
@param {NonNegativeInteger} z.offset - index offset
@param {string} z.order - specifies whether `z` is row-major (C-style) or column-major (Fortran-style)
@param {Array<Function>} z.accessors - data buffer accessors
@param {Callback} fcn - binary callback
@returns {void}

@example
var toAccessorArray = require( '@stdlib/array/base/to-accessor-array' );
var accessors = require( '@stdlib/array/base/accessors' );

function fcn( x, y ) {
    return x + y;
}

// Create data buffers:
var xbuf = toAccessorArray( [ 1.0 ] );
var ybuf = toAccessorArray( [ 2.0 ] );
var zbuf = toAccessorArray( [ 0.0 ] );

// Define the shape of the input and output arrays:
var shape = [];

// Define the array strides:
var sx = [ 0 ];
var sy = [ 0 ];
var sz = [ 0 ];

// Define the index offsets:
var ox = 0;
var oy = 0;
var oz = 0;

// Create the input and output ndarray-like objects:
var x = {
    'dtype': 'generic',
    'data': xbuf,
    'shape': shape,
    'strides': sx,
    'offset': ox,
    'order': 'row-major',
    'accessors': accessors( xbuf ).accessors
};
var y = {
    'dtype': 'generic',
    'data': ybuf,
    'shape': shape,
    'strides': sy,
    'offset': oy,
    'order': 'row-major',
    'accessors': accessors( ybuf ).accessors
};
var z = {
    'dtype': 'generic',
    'data': zbuf,
    'shape': shape,
    'strides': sz,
    'offset': oz,
    'order': 'row-major',
    'accessors': accessors( zbuf ).accessors
};

// Apply the binary function:
binary0d( x, y, z, fcn );

var v = z.data.get( 0 );
// returns 3.0