solve.polynomial {polynom} | R Documentation |
Zeros of a Polynomial
Description
Find the zeros, if any, of a given polynomial.
Usage
## S3 method for class 'polynomial'
solve(a, b, ...)
Arguments
a |
A polynomial object for which the zeros are required. |
b |
a numeric value specifying an additional intercept. If
given, the zeros of |
... |
Not used by this method. |
Details
This is a method for the generic function solve
.
The zeros are found as the eigenvalues of the companion matrix, sorted according to their real parts.
Value
A numeric vector, generally complex, of zeros.
See Also
polyroot
,
poly.calc
,
summary.polynomial
Examples
p <- polynomial(6:1)
p
## 6 + 5*x + 4*x^2 + 3*x^3 + 2*x^4 + x^5
pz <- solve(p)
pz
## [1] -1.49180+0.0000i -0.80579-1.2229i -0.80579+1.2229i
## [4] 0.55169-1.2533i 0.55169+1.2533i
## To retrieve the original polynomial from the zeros:
poly.calc(pz)
## Warning: imaginary parts discarded in coercion
## 6 + 5*x + 4*x^2 + 3*x^3 + 2*x^4 + x^5
[Package polynom version 1.4-1 Index]