function nanrangeBy( N, x, stride, offset, clbk, thisArg ) {
	var max;
	var min;
	var ix;
	var v;
	var i;

	if ( N <= 0 ) {
		return NaN;
	}
	if ( N === 1 || stride === 0 ) {
		v = clbk.call( thisArg, x[ 0 ], 0, 0, x );
		if ( v === void 0 || isnan( v ) ) {
			return NaN;
		}
		return 0.0;
	}
	ix = offset;
	for ( i = 0; i < N; i++ ) {
		min = clbk.call( thisArg, x[ ix ], i, ix, x );
		if ( min === min && min !== void 0 ) {
			break;
		}
		ix += stride;
	}
	if ( i === N ) {
		return NaN;
	}
	max = min;
	i += 1;
	for ( i; i < N; i++ ) {
		ix += stride;
		v = clbk.call( thisArg, x[ ix ], i, ix, x );
		if ( v === void 0 || isnan( v ) ) {
			continue;
		}
		if ( v < min ) {
			min = v;
		} else if ( v > max ) {
			max = v;
		}
	}
	return max - min;
}
Calculates the range of a strided array via a callback function, ignoring `NaN` values.

@param {PositiveInteger} N - number of indexed elements
@param {Collection} x - input array/collection
@param {integer} stride - index increment
@param {NonNegativeInteger} offset - starting index
@param {Callback} clbk - callback
@param {*} [thisArg] - execution context
@returns {number} range

@example
var x = [ -2.0, 1.0, 3.0, -5.0, 4.0, NaN, 0.0, -1.0, -3.0 ];

function accessor( v ) {
    return v * 2.0;
}

var v = nanrangeBy( x.length, x, 1, 0, accessor );
// returns 18.0