How to use the d3-ease.easeQuadInOut function in d3-ease

* Note: These tests are intended to test the definitions only
 * in the sense of typing and call signature consistency. They
 * are not intended as functional tests.
 */

import * as d3Ease from 'd3-ease';

let t_in: number = 0.5;
let t_out: number;

t_out = d3Ease.easeLinear(t_in);

t_out = d3Ease.easeQuad(t_in);
t_out = d3Ease.easeQuadIn(t_in);
t_out = d3Ease.easeQuadOut(t_in);
t_out = d3Ease.easeQuadInOut(t_in);

t_out = d3Ease.easeCubic(t_in);
t_out = d3Ease.easeCubicIn(t_in);
t_out = d3Ease.easeCubicOut(t_in);
t_out = d3Ease.easeCubicInOut(t_in);


let easePolyFactory: d3Ease.PolynomialEasingFactory;

easePolyFactory = d3Ease.easePoly;
easePolyFactory = d3Ease.easePoly.exponent(2);
t_out = easePolyFactory(t_in);

easePolyFactory = d3Ease.easePolyIn;
easePolyFactory = d3Ease.easePolyIn.exponent(2);
t_out = easePolyFactory(t_in);

const updateScroll = e => {
    const pos = scrollSpring.getValue();
    if (pos >= 0 && pos <= 20) {
      let e = easeQuadInOut(pos / 20);
      position = [0, e * -5, e * 15 + 5];
      rotation = [e * -10, 0, 0];
    } else if (pos > 20 && pos <= 40) {
      let e = easeQuadInOut((pos - 20) / 20);
      position = [0, -5 + e * 5, 15 + 5 - e * 15];
      rotation = [-10 + e * -80, 0, 0];

    } else if (pos > 40 && pos <= 90) {
      let e = (pos - 40) / 50;
      position = [0, e * 40, 5];
      rotation = [-90, 0, 0];

    } else if (pos > 90 && pos <= 100) {
      let e = easeQuadOut((pos - 90) / 10);
      position = [0, 40 + e * 5, 5];
      rotation = [-90, 0, 0];