annotate isEquidistant.m @ 1031:2ef20d00b386 feature/advectionRV

For easier comparison, return both the first order and residual viscosity when evaluating the residual. Add the first order and residual viscosity to the state of the RungekuttaRV time steppers
author Vidar Stiernström <vidar.stiernstrom@it.uu.se>
date Thu, 17 Jan 2019 10:25:06 +0100
parents b43c4d841afe
children
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b43c4d841afe Add isEquidistant function for testing vectors
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1 % Tests if consecutive elements of vector v are euidistant
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2 function b = isEquidistant(v)
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3 if length(v) < 2
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4 error('sbplib:isEquidistant:inputTooShort', 'Input vector is too short');
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5 end
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6
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7 tol = 1e-8;
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8
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9 d = v(2:end) - v(1:end-1);
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10 err = abs(d - d(1));
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12 relErr = err./abs(d);
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13
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14 I_zero = find(d < tol);
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16 relErr(I_zero) = err(I_zero);
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17
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18 b = all(relErr < tol);
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19 end