Re: Another AppendTo replacement problem
- To: mathgroup at smc.vnet.net
- Subject: [mg118218] Re: Another AppendTo replacement problem
- From: ADL <alberto.dilullo at tiscali.it>
- Date: Sun, 17 Apr 2011 07:51:20 -0400 (EDT)
- References: <iobv13$bfp$1@smc.vnet.net>
On 16 Apr, 13:37, Iv=E1n Lazaro <gamins... at gmail.com> wrote:
> I made a mistake in the code. Now it's fine. Sorry.
>
> NumBasis = 10000;
> q = matrA = ma = Table[0, {i, 2}];
> M = RandomComplex[{-1 - I, 1 + I}, {NumBasis, 2, 2}];
> M = Map[Orthogonalize, M];
> matr = RandomComplex[{-1 - I, 1 + I}, {2, 2}]
> Results = {};
>
> Do[{ma[[k]] =
> KroneckerProduct[M[[Nbase, k]], Conjugate[M[[Nbase, k]]]];
> matrA[[k]] = Chop[matr.ma[[k]]];
> matrA[[k]] = matrA[[k]]/Tr[matrA[[k]].matrA[[k]]] // Chop;
> If[k == 2,
> AppendTo[
> Results, {M[[Nbase]], Total[Eigenvalues[matrA[[k]]]]}]];
> }, {Nbase, 1, NumBasis}, {k, 1, 2}];
>
> M = Sort[Results, #1[[2]] < #2[[2]] &][[1, 1]];
>
> Thanks in advance!
You might try with Reap and Sow. In my system it is four/five times
faster:
reapVersion := (
NumBasis = 10000;
q = matrA = ma = Table[0, {i, 2}];
M = RandomComplex[{-1 - I, 1 + I}, {NumBasis, 2, 2}];
M = Orthogonalize /@ M;
matr = RandomComplex[{-1 - I, 1 + I}, {2, 2}];
Results =
Last[Reap[
Do[{ma[[k]] = KroneckerProduct[M[[Nbase,k]],
Conjugate[M[[Nbase,k]]]]; matrA[[k]] =
Chop[matr . ma[[k]]]; matrA[[k]] =
Chop[matrA[[k]]/Tr[matrA[[k]] . matrA[[k]]]];
If[k == 2, Sow[{M[[Nbase]], Total[Eigenvalues[
matrA[[k]]]]}]]; }, {Nbase, 1, NumBasis},
{k, 1, 2}]
]];
M=Sort[Results][[1,1]];
M
)