gftool.hermpade.pade_lstsq

gftool.hermpade.pade_lstsq(an, num_deg: int, den_deg: int, rcond=None, fix_q=None) → RatPol[source]

Return the [num_deg/den_deg] Padé approximant to the polynomial an.

Same as pade, however all elements of an are taken into account. Instead of finding the null-vector of the underdetermined system, the parameter RatPol.denom.coeff[0]=1 is fixed and the system is solved truncating small singular values.

Parameters:

an(L,) array_like: Taylor series coefficients representing polynomial of order L-1.
num_deg, den_degint: The order of the return approximating numerator/denominator polynomial. The sum must be at most L: L >= num_deg + den_deg + 1.
rcondfloat, optional: Cut-off ratio for small singular values for the denominator polynomial. For the purposes of rank determination, singular values are treated as zero if they are smaller than rcond times the largest singular value (default: machine precision times den_deg).

Returns:

RatPol: The rational polynomial with numerator RatPol.numer, and denominator RatPol.denom.