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annotate findZeros.m @ 577:e45c9b56d50d feature/grids

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Add an Empty grid class The need turned up for the flexural code when we may or may not have a grid for the open water and want to plot that solution. In case there is no open water we need an empty grid to plot the empty gridfunction against to avoid errors.
author Jonatan Werpers <jonatan@werpers.com>
date Thu, 07 Sep 2017 09:16:12 +0200
parents 8368beb0d1b3
children
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1 % findZeros looks for solutions to the equation f(x)==0 within
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2 % the limits lim with a granularity of h.
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3 % Returns a sorted list of unique solutions.
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4 function z = findZeros(f, lim, h)
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5 n = ceil((lim(2)-lim(1))/h);
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6 z0 = linspace(lim(1), lim(2), n);
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7
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8 z = zeros(1,n);
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9
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10 for i = 1:n
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11 zt(i) = fzero(f, z0(i));
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12 end
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13
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14 zt = sort(zt);
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16 z = [];
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17 for i = 1:n
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18 if zt(i) < lim(1) || zt(i) > lim(2)
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19 continue
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20 end
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21
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22 if ~isempty(z) && abs(z(end) - zt(i)) < 1e-6
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23 continue
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24 end
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25
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26 z = [z zt(i)];
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27 end
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28
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29 % z = unique(z);
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30 end