Mercurial > repos > public > sbplib
changeset 1011:e0560bc4fb7d feature/advectionRV
Add todo:s for time stepping with RV
| author | Vidar Stiernström <vidar.stiernstrom@it.uu.se> |
|---|---|
| date | Thu, 15 Nov 2018 13:49:11 -0800 |
| parents | f753bada1a46 |
| children | 1e437c9e5132 |
| files | +time/+rk/butcherTableau.m +time/RungekuttaRV.m |
| diffstat | 2 files changed, 17 insertions(+), 1 deletions(-) [+] |
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diff -r f753bada1a46 -r e0560bc4fb7d +time/+rk/butcherTableau.m --- a/+time/+rk/butcherTableau.m Wed Nov 07 10:03:35 2018 -0800 +++ b/+time/+rk/butcherTableau.m Thu Nov 15 13:49:11 2018 -0800 @@ -1,5 +1,5 @@ function [s,a,b,c] = butcherTableau(order) - +% TODO: Change order from a double to string. switch order case 3 @@ -19,6 +19,15 @@ a(4,1) = 0; a(4,2) = 0; a(4,3) = 1; b = [1/6 1/3 1/3 1/6]; c = [0, 1/2, 1/2, 1]; + % case 4-3/8 + % % 3/8 RK4 (Kuttas method). Lower truncation error, more flops + % s = 4; + % a = zeros(s,s-1); + % a(2,1) = 1/3; + % a(3,1) = -1/3; a(3,2) = 1; + % a(4,1) = 1; a(4,2) = -1; a(4,3) = 1; + % b = [1/8 3/8 3/8 1/8]; + % c = [0, 1/3, 2/3, 1]; case 6 % Runge-Kutta 6 from Alshina07 s = 7;
diff -r f753bada1a46 -r e0560bc4fb7d +time/RungekuttaRV.m --- a/+time/RungekuttaRV.m Wed Nov 07 10:03:35 2018 -0800 +++ b/+time/RungekuttaRV.m Thu Nov 15 13:49:11 2018 -0800 @@ -37,6 +37,13 @@ obj.v = time.rk.rungekuttaRV(obj.v, obj.t, obj.k, obj.F, obj.RV, obj.coeffs); obj.t = obj.t + obj.k; obj.n = obj.n + 1; + % TBD: Add option for updating the residual inside or outside? Decide on best way to do it? + % v_prev = obj.v; + % F = @(v,t)obj.F(v,t,obj.RV.getViscosity()); + % obj.v = time.rk.rungekutta(obj.v, obj.t, obj.k, F, obj.coeffs); + % obj.RV.update(obj.v,v_prev,obj.k); + % obj.t = obj.t + obj.k; + % obj.n = obj.n + 1; end end