Add docs of AutoSparseForwardDiff and matrix coloring #231
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Signed-off-by: ErikQQY <[email protected]>
Signed-off-by: ErikQQY <[email protected]>
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## master #231 +/- ##
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+ Coverage 19.84% 20.87% +1.03%
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+ Hits 154 162 +8
+ Misses 622 614 -8 see 2 files with indirect coverage changes 📣 We’re building smart automated test selection to slash your CI/CD build times. Learn more |
| colorvec = ArrayInterface.matrix_colors(jac_sparsity) | ||
| ff = NonlinearFunction(brusselator_2d_loop; jac_prototype=float.(jac_sparsity), colorvec) |
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Aren't the color vectors done automatically so this step is unneccessary?
| colorvec = ArrayInterface.matrix_colors(jac_sparsity) | ||
| ff = NonlinearFunction(brusselator_2d_loop; jac_prototype=float.(jac_sparsity), colorvec) |
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Aren't the color vectors done automatically so this step is unneccessary?
| @@ -275,3 +275,28 @@ nothing # hide | |||
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| For more information on the preconditioner interface, see the | |||
| [linear solver documentation](https://docs.sciml.ai/LinearSolve/stable/basics/Preconditioners/). | |||
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| ## Speed up Jacobian computation with sparsity exploitation and matrix coloring | |||
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This seems a bit oddly placed since the parts above already did sparsity and matrix coloring. This is just a less manual route for it
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Avik said the above part https://docs.sciml.ai/NonlinearSolve/dev/tutorials/advanced/#Declaring-a-Sparse-Jacobian-with-Automatic-Sparsity-Detection didn't actually use sparsity, we still need to use sparse AD type for matrix coloring. Did I understand this wrong?
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@ErikQQY is right. Right now even if you have colorvecs and stuff but use a non-sparse AD type, we construct a dense jacobian based on how SparseDiffTools is setup. But this can be modified.
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Oh. We should change that. If you pass a sparse matrix into jac_prototype it should always use sparse diff on it. The SparseDiffTools stuff should only override it to force sparse in the case of jac_prototype=nothing, otherwise it should respect the user's type and color on-demand (since coloring is super cheap).
Continue #213