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annotate +time/Rungekutta4proper.m @ 774:66eb4a2bbb72 feature/grids

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Remove default scaling of the system. The scaling doens't seem to help actual solutions. One example that fails in the flexural code. With large timesteps the solutions seems to blow up. One particular example is profilePresentation on the tdb_presentation_figures branch with k = 0.0005
author Jonatan Werpers <jonatan@werpers.com>
date Wed, 18 Jul 2018 15:42:52 -0700
parents e1a05acc1b5d
children c6fcee3fcf1b 8894e9c49e40
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910a05dcdfdf Added Rk4 as it should be.
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1 classdef Rungekutta4proper < time.Timestepper
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2 properties
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3 F
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7 m
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9 end
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12 methods
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13 % Timesteps v_t = F(v,t), using RK4 fromt t = t0 with timestep k and initial conditions v = v0
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14 function obj = Rungekutta4proper(F, k, t0, v0)
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15 obj.F = F;
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16 obj.k = k;
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17 obj.t = t0;
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18 obj.v = v0;
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19 obj.m = length(v0);
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20 obj.n = 0;
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21 end
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23 function [v,t] = getV(obj)
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24 v = obj.v;
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25 t = obj.t;
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26 end
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28 function obj = step(obj)
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29 obj.v = time.rk4.rungekutta_4(obj.v, obj.t, obj.k, obj.F);
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30 obj.t = obj.t + obj.k;
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31 obj.n = obj.n + 1;
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32 end
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33 end
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36 methods (Static)
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37 function k = getTimeStep(lambda)
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38 k = rk4.get_rk4_time_step(lambda);
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39 end
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40 end
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