annotate +util/matrixborrow.m @ 1289:2fd2e2337b77 feature/boundary_optimized_grids

Add utility function for constructing a (possibly multidimensional) grid based on the grid points used by the boundary optimized SBP operators
author Vidar Stiernström <vidar.stiernstrom@it.uu.se>
date Wed, 01 Jul 2020 15:15:30 +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