H[t_] = {{0, 1}, {1, t}};
tmax=5;
fun[X_?ArrayQ, t_] := -I (H[t].X - X.H[t]);
sol = NDSolve[{σ'[t] == fun[σ[t], t], σ[0] ==
Table[If[i == 1 \[And] j == 1, 1, 0], {i, 1, 2}, {j, 1,
2}]}, σ[t], {t, 0, tmax}]
Flatten[Evaluate[σ[t] /. sol /. {t -> tmax/100}], 1] // MatrixForm
Plot[Table[Flatten[Evaluate[σ[t] /. sol], 1][[i, i]], {i, 1, 2}], {t, 0,tmax}, PlotRange -> All]
How to change the color of two lines in plot... and why
Flatten[Evaluate[σ[t] /. sol], 1][[1, 1]]
gives
t
while
Flatten[Evaluate[σ[t] /. sol], 1][[2, 2]]
gives
{InterpolatingFuction[{{0.,5.}},<>}[t]}[[2,2]]
H[t_] = {{0, 1}, {1, 1}};
? what ist
doing here? $\endgroup$