Mercurial > repos > public > sbplib
annotate +time/+expint/Magnus_mp.m~ @ 696:7c16b5af8d98 feature/quantumTriangles
Add Jonatans symbolic lifehax
author | Ylva Rydin <ylva.rydin@telia.com> |
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date | Thu, 05 Oct 2017 18:04:23 +0200 |
parents | bc39bb984d88 |
children | 8434063ed162 |
rev | line source |
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bc39bb984d88
Added arnoldi krylov subspace approximation
Ylva Rydin <ylva.rydin@telia.com>
parents:
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changeset
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1 % Takes one time step of size k using the magnus midpoinr |
bc39bb984d88
Added arnoldi krylov subspace approximation
Ylva Rydin <ylva.rydin@telia.com>
parents:
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changeset
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2 % starting from v_0 and where the function F(v,t) gives the |
bc39bb984d88
Added arnoldi krylov subspace approximation
Ylva Rydin <ylva.rydin@telia.com>
parents:
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3 % time derivatives. |
bc39bb984d88
Added arnoldi krylov subspace approximation
Ylva Rydin <ylva.rydin@telia.com>
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4 function v = Magnus_mp(v,D, t , k,matrixexp,tol) |
bc39bb984d88
Added arnoldi krylov subspace approximation
Ylva Rydin <ylva.rydin@telia.com>
parents:
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5 |
bc39bb984d88
Added arnoldi krylov subspace approximation
Ylva Rydin <ylva.rydin@telia.com>
parents:
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6 if isa(D,'function_handle') |
bc39bb984d88
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Ylva Rydin <ylva.rydin@telia.com>
parents:
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7 switch matrixexp |
bc39bb984d88
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Ylva Rydin <ylva.rydin@telia.com>
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8 case 'expm' |
bc39bb984d88
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Ylva Rydin <ylva.rydin@telia.com>
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9 v = expm(k*D(t +k/2))*v; |
bc39bb984d88
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Ylva Rydin <ylva.rydin@telia.com>
parents:
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10 case 'Arnol' |
bc39bb984d88
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Ylva Rydin <ylva.rydin@telia.com>
parents:
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11 v = time.expint.expm_Arnoldi(-D(t +k/2),v,k,toler,100); |
bc39bb984d88
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Ylva Rydin <ylva.rydin@telia.com>
parents:
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12 else |
bc39bb984d88
Added arnoldi krylov subspace approximation
Ylva Rydin <ylva.rydin@telia.com>
parents:
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13 %v = krylov(k*D,v); |
bc39bb984d88
Added arnoldi krylov subspace approximation
Ylva Rydin <ylva.rydin@telia.com>
parents:
diff
changeset
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14 % v = expm(k*D)*v; |
bc39bb984d88
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Ylva Rydin <ylva.rydin@telia.com>
parents:
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15 end |
bc39bb984d88
Added arnoldi krylov subspace approximation
Ylva Rydin <ylva.rydin@telia.com>
parents:
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16 |
bc39bb984d88
Added arnoldi krylov subspace approximation
Ylva Rydin <ylva.rydin@telia.com>
parents:
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17 end |