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annotate +time/+expint/Magnus_mp.m @ 696:7c16b5af8d98 feature/quantumTriangles

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Add Jonatans symbolic lifehax
author Ylva Rydin <ylva.rydin@telia.com>
date Thu, 05 Oct 2017 18:04:23 +0200
parents bc39bb984d88
children 8434063ed162
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49bc2929dfb1 Added the midpont magnus exponential integrator
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1 % Takes one time step of size k using the magnus midpoinr
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2 % starting from v_0 and where the function F(v,t) gives the
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3 % time derivatives.
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4 function v = Magnus_mp(v,D, t , k,matrixexp,tol)
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6 if isa(D,'function_handle')
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7 Omega = D(t +k/2);
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8 else
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9 Omega = D;
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10 end
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11
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12 switch matrixexp
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13 case 'expm'
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14 v = expm(k*Omega)*v;
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15 case 'Arnoldi'
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16 v = time.expint.expm_Arnoldi(-Omega,v,k,tol,100);
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17 otherwise
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18 error('No such matrix exponential evaluation')
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19
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20 end
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21 end