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annotate +time/Rungekutta4.m @ 1198:2924b3a9b921 feature/d2_compatible

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Add OpSet for fully compatible D2Variable, created from regular D2Variable by replacing d1 by first row of D1. Formal reduction by one order of accuracy at the boundary point.
author Martin Almquist <malmquist@stanford.edu>
date Fri, 16 Aug 2019 14:30:28 -0700
parents ef5c9870f386
children b5e5b195da1e c6fcee3fcf1b
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1 classdef Rungekutta4 < time.Timestepper
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2 properties
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3 D
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4 S
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5 F
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6 k
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7 t
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8 v
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9 m
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10 n
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11 end
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12
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14 methods
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15 function obj = Rungekutta4(D, S, k, t0, v0)
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16 obj.D = D;
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17 obj.k = k;
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18 obj.t = t0;
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19 obj.v = v0;
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20 obj.m = length(v0);
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21 obj.n = 0;
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22
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23 if S == 0
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24 obj.S = zeros(obj.m,1);
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25 else
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26 obj.S = S;
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27 end
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28
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29 if S == 0
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30 obj.F = @(v,t)(obj.D*v);
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31 else
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32 obj.F = @(v,t)(obj.D*v + obj.S);
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33 end
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34 end
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35
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36 function [v,t] = getV(obj)
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37 v = obj.v;
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38 t = obj.t;
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39 end
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40
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41 function obj = step(obj)
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42 obj.v = time.rk4.rungekutta_4(obj.v, obj.t, obj.k, obj.F);
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43 obj.t = obj.t + obj.k;
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44 obj.n = obj.n + 1;
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45 end
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46 end
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48
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49 methods (Static)
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50 function k = getTimeStep(lambda)
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51 k = rk4.get_rk4_time_step(lambda);
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52 end
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53 end
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54
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55 end