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annotate +time/+rkparameters/rk4.m @ 1339:bcdb14b05d03 feature/D2_boundary_opt

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Fix comment
author Vidar Stiernström <vidar.stiernstrom@it.uu.se>
date Fri, 22 Jul 2022 16:31:18 +0200
parents ee4cfb37534d
children
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ee4cfb37534d Merge with feature/d1_staggered to get RK timestepper for discrete data.
Martin Almquist <malmquist@stanford.edu>
parents:
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1 function [a,b,c,s] = rk4()
ee4cfb37534d Merge with feature/d1_staggered to get RK timestepper for discrete data.
Martin Almquist <malmquist@stanford.edu>
parents:
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2
ee4cfb37534d Merge with feature/d1_staggered to get RK timestepper for discrete data.
Martin Almquist <malmquist@stanford.edu>
parents:
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3 % Butcher tableau for classical RK$
ee4cfb37534d Merge with feature/d1_staggered to get RK timestepper for discrete data.
Martin Almquist <malmquist@stanford.edu>
parents:
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4 s = 4;
ee4cfb37534d Merge with feature/d1_staggered to get RK timestepper for discrete data.
Martin Almquist <malmquist@stanford.edu>
parents:
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5 a = sparse(s,s);
ee4cfb37534d Merge with feature/d1_staggered to get RK timestepper for discrete data.
Martin Almquist <malmquist@stanford.edu>
parents:
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6 a(2,1) = 1/2;
ee4cfb37534d Merge with feature/d1_staggered to get RK timestepper for discrete data.
Martin Almquist <malmquist@stanford.edu>
parents:
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7 a(3,2) = 1/2;
ee4cfb37534d Merge with feature/d1_staggered to get RK timestepper for discrete data.
Martin Almquist <malmquist@stanford.edu>
parents:
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8 a(4,3) = 1;
ee4cfb37534d Merge with feature/d1_staggered to get RK timestepper for discrete data.
Martin Almquist <malmquist@stanford.edu>
parents:
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9 b = 1/6*[1; 2; 2; 1];
ee4cfb37534d Merge with feature/d1_staggered to get RK timestepper for discrete data.
Martin Almquist <malmquist@stanford.edu>
parents:
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10 c = [0; 1/2; 1/2; 1];
ee4cfb37534d Merge with feature/d1_staggered to get RK timestepper for discrete data.
Martin Almquist <malmquist@stanford.edu>
parents:
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11
ee4cfb37534d Merge with feature/d1_staggered to get RK timestepper for discrete data.
Martin Almquist <malmquist@stanford.edu>
parents:
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