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annotate +util/matrixborrow.m @ 888:8732d6bd9890 feature/timesteppers

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Add general Runge-Kutta class - Add a general Runge-Kutta class which time integrates the solution based on coefficients obtained from a Butcher tableau - Add butcher tableau which returns coefficents for the specified Runge-Kutta method - Remove RungKutta4proper, since obsolete
author Vidar Stiernström <vidar.stiernstrom@it.uu.se>
date Thu, 15 Nov 2018 17:10:01 -0800
parents 48b6fb693025
children
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Jonatan Werpers <jonatan@werpers.com>
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1 function alpha = matrixborrow(A,B)
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2
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3 function y = neg(x)
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4 y = min(eig(A-x*B));
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5 end
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6
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7
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8 x0 = 1;
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9 while neg(x0) > -1
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10 x0 = 2*x0;
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11 end
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12
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13 opt = optimset('Display','none');
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14 alpha = fsolve(@neg, x0,opt);
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15 end