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annotate +util/matrixborrow.m @ 1141:91058813b6e7 feature/laplace_curvilinear_test

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Multiply by 2 in VirtaMin so that scheme is actually provably stable.
author Martin Almquist <malmquist@stanford.edu>
date Fri, 21 Jun 2019 17:28:33 +0200
parents 48b6fb693025
children
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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