_₂F₁(-n,1.5,2.5,2) loses accuracy for large n
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Assessment
- Difficulty
- 4/5
- Estimated time
- 3-5 days
- Newbie friendliness
- 35/100
Research direction
Start by reproducing the two Julia expressions for n=0:100 and comparing their values on a logarithmic plot. Inspect the implementation and numerical path for _₂F₁(-n,1.5,2.5,2); done means the expression retains accuracy for large n and agrees with the equivalent formulation.
Written by the indexing model from the issue text.
Description
These two expressions should be identical,
a=[2*sqrt(2)/(n+1)*_₂F₁(1,n+2.5,n+2,-1)+(-1)^n*beta(n+1,1.5) for n=0:100]
c=[2*sqrt(2)*(-1)^n*beta(1.5,1)*_₂F₁(-n,1.5,2.5,2) for n=0:100]
But it turns out that a is more accurate:
plot(abs.([a c]), yaxis=:log, labels=["a" "c"])
- Dominant language
- Julia
- Stars
- 76
- Forks
- 12
- PR merge metrics
- No merged PRs in 30d
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