Find complex roots of polynomials in x that are quadratic
polynomials in x^k
Usage
findRoots(coefs, k = 1)
Value
A list with components
left
The k roots with left most real components
right
The k roots with right most real components
Arguments
coefs
Coefficients (c_0,c_k,c_2k) of quadratic polynomial in
x^k. Also accepts matrix input (J,3).
k
Order of x^k
Author
Bo Markussen <bomar@math.ku.dk>
Details
It is assumed that c_2k is non-zero, and that at least one of
c_0 and c_k are non-zero (otherwise, we have a double
root, which is not treated by fdaLm in the present
implementation). An error is issued if these assumptions are violated.
References
Solved using Section 5.6 in Press et al, "Numerical Recipies in C",
second edition.