let n = 4;
let N = 100;
let x = Array.from(Array(N).keys());
x = x.map( (element) => element * n * 2 * Math.PI / N );
let y = x.map((element) => Math.sin(element));
let a = x.map((element) => Math.cos(element));
let b = x.map((element) => - Math.sin(element));
let c = x.map((element) => - Math.cos(element));

let pyplot = new jsplot();
pyplot.plot(
	x,
	y,
);
pyplot.title('4 sinus');
pyplot.show();
pyplot.plot(
	x,
	y,
);
pyplot.plot(
	x,
	a,
);
pyplot.plot(
	x,
	b,
);
pyplot.plot(
	x,
	c,
);
pyplot.show();