annotate +util/matrixborrow.m @ 86:3c39dd714fb6

In Curve: Added numerical FD differentiation if derivative is not supplied. Added arc length computation based on the derivative. Added arc length parameterization (but this function is very slow.). In +util: Added fzero_vec.m and integral_vec.m, which call fzero and integral but take vector arguments.
author Martin Almquist <martin.almquist@it.uu.se>
date Sun, 29 Nov 2015 14:28:53 +0100
parents 48b6fb693025
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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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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