Feature/ssptables#925
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…ing table for ARKODE_SSP_ESDIRK_9_2_3
| S(\theta,\rho) = \left\{ \eta^I = -a+i b \; :\; a>0,\; b\ge 0,\; |\eta^I|\le \rho,\; \operatorname{atan}\left(\frac{b}{a}\right) \le \theta \right\}. | ||
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| For each ARK method, we overlay plots of the border of :math:`\mathcal{J}_{\theta,\rho}` | ||
| for values :math:`\theta \in \left\{0^o, 20^0, 40^0, 60^0, 80^0\right\}` and |
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I think the most useful angle to include would be 90
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Are all the lines on top of each other? I'm a bit suspicious about the region not changing with theta. Aside from IMEX Euler, I've never seen this happen.
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The thicker lines are much easier to see. If it's not too much of hassle, this would be nice for the other plots
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| ARK_BUTCHER_TABLE(ARKODE_ASCHER_SDIRK_3_1_2, { /* https://doi.org/10.1016/S0168-9274(97)00056-1 (custom embedding) */ | ||
| ARKodeButcherTable B = ARKodeButcherTable_Alloc(3, SUNTRUE); | ||
| const sunrealtype gamma = SUN_RCONST(1.0) - SUN_RCONST(1.0) / SUNRsqrt(SUN_RCONST(2.0)); |
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| const sunrealtype gamma = SUN_RCONST(1.0) - SUN_RCONST(1.0) / SUNRsqrt(SUN_RCONST(2.0)); | |
| const sunrealtype gamma = SUN_RCONST(0.29289321881345247559915563789515096071516); |
I recommend avoiding compound floating point operations for coefficients. You can lose the last couple binary digits. I've encountered a few cases in single precision where this was significant. There are a few other cases in this and the erk file.
| ``ARKODE_SSP_LSPUM_ERK_3_1_2`` + ``ARKODE_SSP_LSPUM_SDIRK_3_1_2``, | ||
| and ``ARKODE_ASCHER_ERK_3_1_2`` + ``ARKODE_ASCHER_SDIRK_3_1_2``. | ||
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| Added the ``ARKODE_IMEX_MRI_GARK_ARS222`` and ``ARKODE_IMEX_MRI_GARK_GIRALDO`` |
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I didn't see these in the docs
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This PR adds new Butcher tables to ARKODE. The focus is on explicit, diagonally implicit, and additive RK tables that satisfy strong stability preservation properties.