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annotate +time/Rungekutta.m @ 1031:2ef20d00b386 feature/advectionRV

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For easier comparison, return both the first order and residual viscosity when evaluating the residual. Add the first order and residual viscosity to the state of the RungekuttaRV time steppers
author Vidar Stiernström <vidar.stiernstrom@it.uu.se>
date Thu, 17 Jan 2019 10:25:06 +0100
parents 4e5e53d6336c
children
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846
c6fcee3fcf1b Add generalized RungeKutta and RungeKuttaRV class which extracts its coefficients from a butcher tableau, specified on the scheme.
Vidar Stiernström <vidar.stiernstrom@it.uu.se>
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1 classdef Rungekutta < time.Timestepper
c6fcee3fcf1b Add generalized RungeKutta and RungeKuttaRV class which extracts its coefficients from a butcher tableau, specified on the scheme.
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2 properties
c6fcee3fcf1b Add generalized RungeKutta and RungeKuttaRV class which extracts its coefficients from a butcher tableau, specified on the scheme.
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3 F % RHS of the ODE
c6fcee3fcf1b Add generalized RungeKutta and RungeKuttaRV class which extracts its coefficients from a butcher tableau, specified on the scheme.
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4 k % Time step
c6fcee3fcf1b Add generalized RungeKutta and RungeKuttaRV class which extracts its coefficients from a butcher tableau, specified on the scheme.
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5 t % Time point
c6fcee3fcf1b Add generalized RungeKutta and RungeKuttaRV class which extracts its coefficients from a butcher tableau, specified on the scheme.
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6 v % Solution vector
c6fcee3fcf1b Add generalized RungeKutta and RungeKuttaRV class which extracts its coefficients from a butcher tableau, specified on the scheme.
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7 n % Time level
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4e5e53d6336c Correct documentation of Rungekutta
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8 scheme % The scheme used for the time stepping, e.g rk4, rk6 etc.
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c6fcee3fcf1b Add generalized RungeKutta and RungeKuttaRV class which extracts its coefficients from a butcher tableau, specified on the scheme.
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9 end
c6fcee3fcf1b Add generalized RungeKutta and RungeKuttaRV class which extracts its coefficients from a butcher tableau, specified on the scheme.
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10
c6fcee3fcf1b Add generalized RungeKutta and RungeKuttaRV class which extracts its coefficients from a butcher tableau, specified on the scheme.
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11
c6fcee3fcf1b Add generalized RungeKutta and RungeKuttaRV class which extracts its coefficients from a butcher tableau, specified on the scheme.
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12 methods
c6fcee3fcf1b Add generalized RungeKutta and RungeKuttaRV class which extracts its coefficients from a butcher tableau, specified on the scheme.
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13 % Timesteps v_t = F(v,t), using RK with specfied order from t = t0 with
c6fcee3fcf1b Add generalized RungeKutta and RungeKuttaRV class which extracts its coefficients from a butcher tableau, specified on the scheme.
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14 % timestep k and initial conditions v = v0
c6fcee3fcf1b Add generalized RungeKutta and RungeKuttaRV class which extracts its coefficients from a butcher tableau, specified on the scheme.
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15 function obj = Rungekutta(F, k, t0, v0, order)
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1c6f1595bb94 Clean up in RK time stepper schemes
Vidar Stiernström <vidar.stiernstrom@it.uu.se>
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16 default_arg('order',4);
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c6fcee3fcf1b Add generalized RungeKutta and RungeKuttaRV class which extracts its coefficients from a butcher tableau, specified on the scheme.
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17 obj.F = F;
c6fcee3fcf1b Add generalized RungeKutta and RungeKuttaRV class which extracts its coefficients from a butcher tableau, specified on the scheme.
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18 obj.k = k;
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19 obj.t = t0;
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20 obj.v = v0;
c6fcee3fcf1b Add generalized RungeKutta and RungeKuttaRV class which extracts its coefficients from a butcher tableau, specified on the scheme.
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21 obj.n = 0;
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5b180c76578e Use the old implementation for RK4 until the different methods are profiled.
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parents: 847
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22 % TBD: Order 4 is also implemented in the butcher tableau, but the rungekutta_4.m implementation
5b180c76578e Use the old implementation for RK4 until the different methods are profiled.
Vidar Stiernström <vidar.stiernstrom@it.uu.se>
parents: 847
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23 % might be slightly more efficient. Need to do some profiling before deciding whether or not to keep it.
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24 if (order == 4)
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25 obj.scheme = @time.rk.rungekutta_4;
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Vidar Stiernström <vidar.stiernstrom@it.uu.se>
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26 else
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27 % Extract the coefficients for the specified order
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parents: 847
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28 % used for the RK updates from the Butcher tableua.
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29 [s,a,b,c] = time.rk.butcherTableau(order);
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30 coeffs = struct('s',s,'a',a,'b',b,'c',c);
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31 obj.scheme = @(v,t,dt,F) time.rk.rungekutta(v, t , dt, F, coeffs);
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32 end
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c6fcee3fcf1b Add generalized RungeKutta and RungeKuttaRV class which extracts its coefficients from a butcher tableau, specified on the scheme.
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33 end
c6fcee3fcf1b Add generalized RungeKutta and RungeKuttaRV class which extracts its coefficients from a butcher tableau, specified on the scheme.
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34
c6fcee3fcf1b Add generalized RungeKutta and RungeKuttaRV class which extracts its coefficients from a butcher tableau, specified on the scheme.
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35 function [v,t] = getV(obj)
c6fcee3fcf1b Add generalized RungeKutta and RungeKuttaRV class which extracts its coefficients from a butcher tableau, specified on the scheme.
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36 v = obj.v;
c6fcee3fcf1b Add generalized RungeKutta and RungeKuttaRV class which extracts its coefficients from a butcher tableau, specified on the scheme.
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37 t = obj.t;
c6fcee3fcf1b Add generalized RungeKutta and RungeKuttaRV class which extracts its coefficients from a butcher tableau, specified on the scheme.
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38 end
c6fcee3fcf1b Add generalized RungeKutta and RungeKuttaRV class which extracts its coefficients from a butcher tableau, specified on the scheme.
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39
c6fcee3fcf1b Add generalized RungeKutta and RungeKuttaRV class which extracts its coefficients from a butcher tableau, specified on the scheme.
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40 function obj = step(obj)
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41 obj.v = obj.scheme(obj.v, obj.t, obj.k, obj.F);
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c6fcee3fcf1b Add generalized RungeKutta and RungeKuttaRV class which extracts its coefficients from a butcher tableau, specified on the scheme.
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42 obj.t = obj.t + obj.k;
c6fcee3fcf1b Add generalized RungeKutta and RungeKuttaRV class which extracts its coefficients from a butcher tableau, specified on the scheme.
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43 obj.n = obj.n + 1;
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44 end
c6fcee3fcf1b Add generalized RungeKutta and RungeKuttaRV class which extracts its coefficients from a butcher tableau, specified on the scheme.
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45 end
c6fcee3fcf1b Add generalized RungeKutta and RungeKuttaRV class which extracts its coefficients from a butcher tableau, specified on the scheme.
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46 end