// //--------------------------
// // SUPERSEDED BY `eTaylorShift` !!
// //--------------------------

// import { expansionProduct } from "big-float-ts";
// import { fastExpansionSum } from "big-float-ts";
// import { scaleExpansion2 } from "big-float-ts";


// /**
//  * Returns the exact result (bar undeflow / overflow) of performing a change of 
//  * variables of the form: p(x) <- p(x + b) on the given polynomial (with
//  * coefficients given as Shewchuk expansions).
//  * 
//  * * see [this stackoverflow question](http://stackoverflow.com/questions/141422/how-can-a-transform-a-polynomial-to-another-coordinate-system)
//  * 
//  * @param p a polynomial with coefficients given densely as an array of Shewchuk
//  * floating point expansions from highest to lowest power, e.g. `[[5],[-3],[0]]`
//  * represents the polynomial `5x^2 - 3x`
//  * @param b the `b` in `x + b`
//  * 
//  * @doc
//  */
// function eChangeVariablesTranslateX(
//         p: number[][], 
//         b: number): number[][] {

//     // We let the coefficients of p(x + b) be denoted by d_i in the code below. 
//     // d_i is calculated as d = T*c, where c are the original coefficients.
    
//     const d = p.length-1;

//     if (d < 0) { return []; }

//     // Initialize a zero matrix
//     const t = new Array<number[][]>(d+1);
//     for (let i=0; i<d+1; i++) {
//         t[i] = new Array(d+1).fill([0]);
//     }

//     // Calculate the triangular matrix T
//     t[0][0] = [1];
//     for (let j=1; j<=d; j++) {
//         t[0][j] = scaleExpansion2(b, t[0][j-1]);
//         for (let i=1; i<=j; i++) {
//             t[i][j] = fastExpansionSum(
//                 scaleExpansion2(b, t[i][j-1]), 
//                 t[i-1][j-1]
//             );
//         }
//     }

//     // Multiply
//     const res: number[][] = new Array(d+1).fill([0]);
//     for (let i=0; i<=d; i++) {
//         res[d-i] = [0];
//         for (let j=i; j<=d; j++) {
//             const acc = expansionProduct(t[i][j], p[d-j]);
//             res[d-i] = fastExpansionSum(res[d-i], acc);
//         }
//     }

//     return res;
// }


// export { eChangeVariablesTranslateX }