Update QNDF to new nlsolver #1165
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How's the latest benchmark? I assume that this would "fix it". |
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Before: After: |
| @.. tmp = (uprev + tm - ϕ)/ (dt * β₀) | ||
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| else | ||
| dz = nlsolver.cache.dz |
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I am out of sync due to the MLH things, but we don't handle mass matrix intrinsically in nlsolve? tmp depending on mass matrix sounds spectical
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Alright 👍 I need to see the new nlsolver changes.
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| @test _norm_dsol(QNDF1(),prob,prob2) ≈ 0 atol=1e-12 | ||
| @test _norm_dsol(QNDF2(),prob,prob2) ≈ 0 atol=1e-12 | ||
| @test _norm_dsol(QNDF(),prob,prob2) ≈ 0 atol=1e-7 | ||
| @test _norm_dsol(QNDF(),prob,prob2) ≈ 0 atol=1e-12 |
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I updated the plots slightly for better comparison (due to ode15s). |
| nlsolver.z = uprev + sum(D) | ||
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| mass_matrix = f.mass_matrix | ||
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| if mass_matrix == I | ||
| nlsolver.tmp = @.. (u₀ - ϕ)/ (dt * β₀) | ||
| else | ||
| _tmp = mass_matrix * @.. (u₀ - ϕ) | ||
| nlsolver.tmp = @.. _tmp / (dt * β₀) | ||
| end | ||
| nlsolver.γ = β₀ | ||
| nlsolver.α = α₀ | ||
| nlsolver.method = COEFFICIENT_MULTISTEP |
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I'm a bit surprised about the mix of broadcasted and non-broadcasted expressions (not only in these lines, here it would be just uprev .+ sum(D), but also above e.g. in ϕ += γₖ[i] * D[i]). Shouldn't we consistently use broadcasting? Or does it still impact performance?
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Yeah I agree, actually, there's some dimensional problem like that D is 1x5 matrix and γ is 6-Array, hence probably the person who did before looped using []; it was originally defined like that. We can change it probably for more consistent operation using broadcast, maybe in another PR.
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Why are there two QNDFs in the plots? Is it one QNDF and one QBDF? Which one is better? The WPD curve looks really suspicious since the convergence looks erratic. |
The 'inverted green triangle' legend is QBDF and the other one is QNDF. |
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Do you mind to benchmark |
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Looks like it didn't move... which is odd. |
Before:
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What's the benchmark problem? |
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POLLU, with |
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