function nanvariance( N, correction, x, stride, offset ) {
	return nanvariancepn( N, correction, x, stride, offset );
}
Computes the variance of a strided array ignoring `NaN` values.

@param {PositiveInteger} N - number of indexed elements
@param {number} correction - degrees of freedom adjustment
@param {NumericArray} x - input array
@param {integer} stride - stride length
@param {NonNegativeInteger} offset - starting index
@returns {number} variance

@example
var floor = require( '@stdlib/math/base/special/floor' );

var x = [ 2.0, 1.0, 2.0, -2.0, -2.0, 2.0, 3.0, 4.0, NaN, NaN ];
var N = floor( x.length / 2 );

var v = nanvariance( N, 1, x, 2, 1 );
// returns 6.25