Given n recurrence compute up to Pn #16
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| evaluates the first `N` orthogonal polynomials at point `x`, | ||
| where `A`, `B`, and `C` are `AbstractVector`s containing the first form recurrence coefficients as defined in | ||
| [DLMF](https://dlmf.nist.gov/18.9), i.e. it returns Pᵢ(x) for i = 0, 1, ..., N-1 | ||
| """ | ||
| forwardrecurrence(N::Integer, A::AbstractVector, B::AbstractVector, C::AbstractVector, x) = |
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Should the meaning of N change here? Currently it means compute the first N (including P0) vs compute up to PN. To me, the later makes more sense.
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Julia uses 1-based indexing so I think N specifying the length of the vector is more natural
| @test clenshaw(vec(clenshaw(coeffs, x; dims=1)), A, B, C, y) ≈ clenshaw(vec(clenshaw(coeffs, A, B, C, y; dims=2)), x) ≈ | ||
| only(clenshaw!([0.0], clenshaw!(Matrix{Float64}(undef,1,n), coeffs, x), A, B, C, y)) ≈ | ||
| only(clenshaw!([0.0], clenshaw!(Matrix{Float64}(undef,m,1), coeffs, A, B, C, y), x)) ≈ | ||
| forwardrecurrence(A_T, B_T, C_T, x)'coeffs*forwardrecurrence(A, B, C, y) | ||
| forwardrecurrence(A_T, B_T, C_T, x)'coeffs*forwardrecurrence(A, B, C, y)[1:end-1] |
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I don't understand the clenshaw code enough to know if a similar change is needed there. In order to pass tests I am dropping the last element of forwardrecurrence to replicate the previous behavior.
From looking at clenshaw it seems that P0 isn't explicitly included, while it is in forwardrecurrence. Ideally, they would be consistent, but I'm not familiar with this domain enough to address it.
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Since clenshaw returns a single value there's no point in including p0 as you can just multiply the returned value by p0
Codecov ReportAll modified and coverable lines are covered by tests ✅
Additional details and impacted files@@ Coverage Diff @@
## main #16 +/- ##
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+ Coverage 99.44% 100.00% +0.55%
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Files 7 7
Lines 181 186 +5
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+ Hits 180 186 +6
+ Misses 1 0 -1 ☔ View full report in Codecov by Sentry. |
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@dlfivefifty I took this "PR" out of draft mode. If you are happy with it, it is ready to merge. |
Fixes #15