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annotate +time/+rkparameters/rk4.m @ 753:44c46bd6913a feature/d1_staggered

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Fix stage rate bug in RK4 discrete data
author Martin Almquist <malmquist@stanford.edu>
date Fri, 15 Jun 2018 13:02:29 -0700
parents 9c3c180c7ed3
children
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690
9c3c180c7ed3 Implement RK4 for discrete data.
Martin Almquist <malmquist@stanford.edu>
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1 function [a,b,c,s] = rk4()
9c3c180c7ed3 Implement RK4 for discrete data.
Martin Almquist <malmquist@stanford.edu>
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2
9c3c180c7ed3 Implement RK4 for discrete data.
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3 % Butcher tableau for classical RK$
9c3c180c7ed3 Implement RK4 for discrete data.
Martin Almquist <malmquist@stanford.edu>
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4 s = 4;
9c3c180c7ed3 Implement RK4 for discrete data.
Martin Almquist <malmquist@stanford.edu>
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5 a = sparse(s,s);
9c3c180c7ed3 Implement RK4 for discrete data.
Martin Almquist <malmquist@stanford.edu>
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6 a(2,1) = 1/2;
9c3c180c7ed3 Implement RK4 for discrete data.
Martin Almquist <malmquist@stanford.edu>
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7 a(3,2) = 1/2;
9c3c180c7ed3 Implement RK4 for discrete data.
Martin Almquist <malmquist@stanford.edu>
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8 a(4,3) = 1;
9c3c180c7ed3 Implement RK4 for discrete data.
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9 b = 1/6*[1; 2; 2; 1];
9c3c180c7ed3 Implement RK4 for discrete data.
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10 c = [0; 1/2; 1/2; 1];
9c3c180c7ed3 Implement RK4 for discrete data.
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11
9c3c180c7ed3 Implement RK4 for discrete data.
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12 end