from-roots
▸ function fromRoots
(roots: number[]): number[]
Defined in roots/from-roots/double/from-roots.ts:34
Constructs a polynomial from the given roots by multiplying out the factors (x - root1)(x - root2) in double precision
the resulting polynomial may have complex roots close to zero due to round-off caused by working in double precision.
mostly for testing purposes.
the real roots of the constructed polynomial is unlikely to be exactly the same as the roots that the polynomial has been constructed from due to floating-point round-off.
example
fromRoots([1,2,3,3]); //=> [1, -9, 29, -39, 18]
allRoots([1, -9, 29, -39, 18]); //=> [1.0000000000000007, 2.000000000000004]
// In the above note the rounding error. Also note the multiple root of 3 that has been missed.
allRoots([1, -9, 29, -39, 17.99999999999999]); //=> [0.9999999999999973, 2.00000000000002, 2.9999999999999982]
allRoots([1, -9, 29, -39, 17.9999999999999]); //=> [0.999999999999975, 2.0000000000000986, 2.9999997898930832, 3.0000002095475775]
Parameters:
| Name | Type | Description |
|---|---|---|
roots | number[] | an array of roots |
Returns: number[]