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annotate +sbp/D1Gauss.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 e1d11b6a68d8
children
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4d9d8064e58b Implementation of D1 based on Gauss quadrature formula with 4 nodes.
Martin Almquist <martin.almquist@it.uu.se>
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1 classdef D1Gauss < sbp.OpSet
4d9d8064e58b Implementation of D1 based on Gauss quadrature formula with 4 nodes.
Martin Almquist <martin.almquist@it.uu.se>
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2 % Diagonal-norm SBP operators based on the Gauss quadrature formula
4d9d8064e58b Implementation of D1 based on Gauss quadrature formula with 4 nodes.
Martin Almquist <martin.almquist@it.uu.se>
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3 % with m nodes, which is of degree 2m-1. Hence, The operator D1 is
4d9d8064e58b Implementation of D1 based on Gauss quadrature formula with 4 nodes.
Martin Almquist <martin.almquist@it.uu.se>
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4 % accurate of order m.
4d9d8064e58b Implementation of D1 based on Gauss quadrature formula with 4 nodes.
Martin Almquist <martin.almquist@it.uu.se>
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5 properties
4d9d8064e58b Implementation of D1 based on Gauss quadrature formula with 4 nodes.
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6 D1 % SBP operator approximating first derivative
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Martin Almquist <martin.almquist@it.uu.se>
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7 H % Norm matrix
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8 HI % H^-1
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9 Q % Skew-symmetric matrix
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10 e_l % Left boundary operator
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Martin Almquist <martin.almquist@it.uu.se>
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11 e_r % Right boundary operator
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12 m % Number of grid points.
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13 h % Step size
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14 x % grid
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15 borrowing % Struct with borrowing limits for different norm matrices
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16 end
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17
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18 methods
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Martin Almquist <martin.almquist@it.uu.se>
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19 function obj = D1Gauss(m,lim)
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20
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Martin Almquist <martin.almquist@it.uu.se>
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21 x_l = lim{1};
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22 x_r = lim{2};
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23 L = x_r-x_l;
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24
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25 switch m
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26 case 4
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27 [obj.D1,obj.H,obj.x,obj.h,obj.e_l,obj.e_r] = ...
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42c4f0b545d6 Remove m as input to implementation function. Fix error message for invalid m to D1Gauss
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28 sbp.implementations.d1_gauss_4(L);
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29 otherwise
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42c4f0b545d6 Remove m as input to implementation function. Fix error message for invalid m to D1Gauss
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30 error('Invalid number of points: %d.', m);
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31 end
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34 obj.x = obj.x + x_l;
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35 obj.HI = inv(obj.H);
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36 obj.Q = obj.H*obj.D1 - obj.e_r*obj.e_r' + obj.e_l*obj.e_l';
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37
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38 obj.borrowing = [];
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39 end
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e1d11b6a68d8 Add string methods to OpSets that are missing them
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e1d11b6a68d8 Add string methods to OpSets that are missing them
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41 function str = string(obj)
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42 str = [class(obj) '_' num2str(obj.order)];
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43 end
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44 end
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45 end