e-num-roots
▸ function eNumRoots
(p: number[][]): number
Defined in roots/descartes/expansion/e-num-roots.ts:35
Returns the exact number of distinct real roots in the interval (-∞,+∞) of the given polynomial - subject to floating point underflow / overflow of intermediate calculations.
- From Wikipedia: "In the case of a non-square-free polynomial, if neither a nor b is a multiple root of p, then V(a) − V(b) is the number of distinct real roots of P".
example
const p = [[1], [1], [-64], [236], [-240]];
eNumRoots(p); //=> 4
Parameters:
| Name | Type | Description |
|---|---|---|
p | number[][] | a polynomial with coefficients given densely as an array of Shewchuk expansions from highest to lowest power, e.g. [[5],[-3],[0]] represents the polynomial 5x^2 - 3x |
Returns: number