Mercurial > repos > public > sbplib
annotate +time/+rkparameters/rk4.m @ 1264:066fdfaa2411 feature/poroelastic
Add staggered Lebedev scheme for Cartesian anisotropic. Traction BC work!
| author | Martin Almquist <malmquist@stanford.edu> |
|---|---|
| date | Wed, 29 Apr 2020 21:05:01 -0700 |
| parents | ee4cfb37534d |
| children |
| rev | line source |
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856
ee4cfb37534d
Merge with feature/d1_staggered to get RK timestepper for discrete data.
Martin Almquist <malmquist@stanford.edu>
parents:
diff
changeset
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1 function [a,b,c,s] = rk4() |
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ee4cfb37534d
Merge with feature/d1_staggered to get RK timestepper for discrete data.
Martin Almquist <malmquist@stanford.edu>
parents:
diff
changeset
|
2 |
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ee4cfb37534d
Merge with feature/d1_staggered to get RK timestepper for discrete data.
Martin Almquist <malmquist@stanford.edu>
parents:
diff
changeset
|
3 % Butcher tableau for classical RK$ |
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ee4cfb37534d
Merge with feature/d1_staggered to get RK timestepper for discrete data.
Martin Almquist <malmquist@stanford.edu>
parents:
diff
changeset
|
4 s = 4; |
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ee4cfb37534d
Merge with feature/d1_staggered to get RK timestepper for discrete data.
Martin Almquist <malmquist@stanford.edu>
parents:
diff
changeset
|
5 a = sparse(s,s); |
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ee4cfb37534d
Merge with feature/d1_staggered to get RK timestepper for discrete data.
Martin Almquist <malmquist@stanford.edu>
parents:
diff
changeset
|
6 a(2,1) = 1/2; |
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ee4cfb37534d
Merge with feature/d1_staggered to get RK timestepper for discrete data.
Martin Almquist <malmquist@stanford.edu>
parents:
diff
changeset
|
7 a(3,2) = 1/2; |
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ee4cfb37534d
Merge with feature/d1_staggered to get RK timestepper for discrete data.
Martin Almquist <malmquist@stanford.edu>
parents:
diff
changeset
|
8 a(4,3) = 1; |
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ee4cfb37534d
Merge with feature/d1_staggered to get RK timestepper for discrete data.
Martin Almquist <malmquist@stanford.edu>
parents:
diff
changeset
|
9 b = 1/6*[1; 2; 2; 1]; |
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ee4cfb37534d
Merge with feature/d1_staggered to get RK timestepper for discrete data.
Martin Almquist <malmquist@stanford.edu>
parents:
diff
changeset
|
10 c = [0; 1/2; 1/2; 1]; |
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ee4cfb37534d
Merge with feature/d1_staggered to get RK timestepper for discrete data.
Martin Almquist <malmquist@stanford.edu>
parents:
diff
changeset
|
11 |
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ee4cfb37534d
Merge with feature/d1_staggered to get RK timestepper for discrete data.
Martin Almquist <malmquist@stanford.edu>
parents:
diff
changeset
|
12 end |
