Re: [Boost-users] Boost_1_54_0: boost::math::sph_bessel(n, x) crash at x=0 n>0

Subject: Re: [Boost-users] Boost_1_54_0: boost::math::sph_bessel(n, x) crash at x=0 n>0
From: John Maddock (john_at_[hidden])
Date: 2013-10-18 05:01:47

>1) in your patch for T operator()() part, what's the "n" variable, looking 
>at 1_54_0 version there is no mention to this variable.

There are no changes to operator()(), the n variable appears in the next 
part of the diff in

inline T sph_bessel_j_imp(unsigned n, T x, const Policy& pol)

>2) is there a way to get your current version of the bessel.hpp file ?

Attached.

Note I had to change the previous fix somewhat as it failed for types with 
extended exponent ranges (I realised that just as I was dozing off to sleep 
last night!)

>That's true that for x close to zero but positive there are also problems 
>to the use of power series close to 0 is certainly the best thing to do. I 
>am astonished that this not yet used.

Sorry I don't understand: the problem was occurring inside the power series 
for small x.

John.