时间戳

首页 > 解决方案 > 如何使用“For-Loop”优化我的代码？

for-loop - 如何使用“For-Loop”优化我的代码？

问题描述

我正在尝试开发一种代码来计算材料中电子状态的局部密度。为此，我使用了多个 for 循环和多个表。完成需要 45 秒，我需要更少的时间。任何关于如何优化此代码的建议。

AbsoluteTiming[Ns=2; \[Eta] = 0.001;
Nx=15;
Ny=15;
NN=Nx*Ny;
Nband=8; 
kkmx = Ns*Nx; 
kkmy = Ns*Ny; 
wmax = 0.2; nw = 800; p = 0; 
Print["starting ldos calc"];
nsite = 2; 
ldos  = 0; 

For[kx = 0, kx <= (Ns - 1.)*2*(Pi/kkmx), kx += 2*(Pi/kkmx),
For[ky = 0, ky <= (Ns - 1.)*2*(Pi/kkmy), ky += 2*(Pi/kkmy),
ES = Eigensystem[H];
elist = Table[ES[[1,l]], {l, 1, Nband/2*4*NN}];
 ulist = Table[Abs[ES[[2,l,i]]]^2, {l, 1, Nband/2*4*NN}, {i, 388+1, 388+(nsite - 1)*Nband/2 + Nband/2}]; 
   vlist = Table[Abs[ES[[2,l,i + Nband/2*NN*2]]]^2, {l, 1, Nband/2*4*NN}, {i, 388+1, 388+(nsite - 1)*Nband/2 + Nband/2}]; 

   ldossc = Table[Im[Total[Table[ulist[[l,1 ;; All]]*(1/(-wmax + wmax*2*(w/nw) - elist[[l]] + I*\[Eta])) + 
   vlist[[l,1 ;; All]]*(1/(-wmax + 2*wmax*(w/nw) + elist[[l]] + I*\[Eta])), {l, 1, Nband/2*4*NN}]]], {w, 0, nw}]; ldos = ldos + ldossc; 

   Export["ldosorb_up_P.dat", Table[{-wmax + wmax*2*(\[Omega]/nw), (-Pi^(-1))*(ldos[[\[Omega] + 1,i]]/Ns^2)}, {\[Omega], 0, nw}, {i, 1,8}]]; 
  (* Export["ldostot.dat", Table[{-wmax + wmax*2*(\[Omega]/nw), (-Pi^(-1))*((ldos[[\[Omega] + 1,i]] + ldos[[\[Omega] + 1,i + 1]] + ldos[[\[Omega] + 1,i + 2]] + ldos[[\[Omega] + 1,i + 3]] + ldos[[\[Omega] + 1,i + 4]])/Ns^2)}, {\[Omega], 0, nw}, {i, 1, (nsite - 1)*Nband/2 + Nband/2 - 4}]]; *)
   Print["kx=", kx, "   ky=", ky, "  nsx=", (kx/(2*Pi))*kkmx + 1.]; ]; ]; ]```

标签： for-loopoptimizationtimeparallel-processingwolfram-mathematica

解决方案

推荐阅读