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annotate +time/+rk4/get_rk4_time_step.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 48b6fb693025
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1 % Calculate the size of the largest time step given the largest evalue for a operator with pure imaginary e.values.
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2 function k = get_rk4_time_step(lambda,l_type)
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3 default_arg('l_type','complex')
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4
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5 rad = abs(lambda);
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6 if strcmp(l_type,'real')
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7 % Real eigenvalue
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8 % kl > -2.7852
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9 k = 2.7852/rad;
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10
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11 elseif strcmp(l_type,'imag')
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12 % Imaginary eigenvalue
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13 % |kl| < 2.8284
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14 k = 2.8284/rad;
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15 elseif strcmp(l_type,'complex')
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16 % |kl| < 2.5
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17 k = 2.5/rad;
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18 else
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19 error('l_type must be one of ''real'',''imag'' or ''complex''.')
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20 end
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21 end