use full and understandable names

[targos]

savitzky-golay/src/index.js

Lines 11 to 14 in a7c7e9f

	function SavitzkyGolay (y, dx) {
	this.data = y;
	this.h = dx
	}

savitzky-golay/src/index.js

Lines 16 to 20 in a7c7e9f

	var defaultOptions = {
	windSize: 5,
	deriv: 1,
	pol: 2
	};