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annotate +time/+expint/Magnus_mp.m @ 512:4ef2d2a493f1 feature/quantumTriangles

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add H_xyz to hypsyst to compute H-norm
author Ylva Rydin <ylva.rydin@telia.com>
date Mon, 26 Jun 2017 19:23:19 +0200
parents 566304a5733e
children bc39bb984d88
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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
49bc2929dfb1 Added the midpont magnus exponential integrator
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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)
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5
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6 if isa(D,'function_handle')
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7 % v = krylov(k*D(t +k/2*t),v);
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8 % v = expm(k*D(t +k/2))*v;
4ef2d2a493f1 add H_xyz to hypsyst to compute H-norm
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9 toler = 10^(-5);
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10 expm_Arnoldi(-D,v,k,toler,100)
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11 else
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12 %v = krylov(k*D,v);
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13 % v = expm(k*D)*v;
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14 end
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16 end