[Scipy-tickets] [SciPy] #787: Spurious inf from scipy.special.hyp1f1(0, -k, z)
SciPy
scipy-tickets@scipy....
Sun Nov 9 19:09:00 CST 2008
#787: Spurious inf from scipy.special.hyp1f1(0, -k, z)
---------------------------+------------------------------------------------
Reporter: pv | Owner: somebody
Type: defect | Status: new
Priority: normal | Milestone: 0.8
Component: scipy.special | Version: devel
Severity: minor | Keywords:
---------------------------+------------------------------------------------
hyp1f1(a=0, b, z) yields infs at points which are poles for a != 0:
{{{
>>> s.hyp1f1(0, -0.99999, 0)
1.0
>>> s.hyp1f1(0, -1, 0)
inf
>>> s.hyp1f1(0, -1.00001, 0)
1.0
}}}
It would make sense to continue hyp1f1(0, b, z) to unity with all b, z for
a=0. See eg.
http://functions.wolfram.com/HypergeometricFunctions/Hypergeometric1F1/03/01/03/0003/
-- this convention is used also by Mathematica.
--
Ticket URL: <http://scipy.org/scipy/scipy/ticket/787>
SciPy <http://www.scipy.org/>
SciPy is open-source software for mathematics, science, and engineering.
More information about the Scipy-tickets
mailing list