Question

这是我的实际代码：

Lr = linspace(100,300,10);
vi = linspace(10,30,10);
vf = linspace(10,30,10);
b = linspace(0.5,1.2,10);
h = linspace(0.3,0.8,10);
Rc = [1000, 1500, 2000, 2500, 3000, 3500;
      29, 22.4, 17.3, 13.4, 10.4, 8];
rti = randi(5, 10, 1, 10, 10, 10, 10);
for kk = 1:rows(Lr)
  for jj = 1:length(vi)
    for ll = 1:length(vf)
      for mm = 1:length(b)
        for nn = 1:length(h)
          ratt(kk,1,jj,ll,mm,nn) = Rc(2,rti(kk,1,jj,ll,mm,nn));
        endfor
      endfor
    endfor
  endfor
endfor

在此示例中，所有向量的长度均为10，但在实际代码中，它们的长度可以为1至100。如何删除所有这些循环？

Answer 1

将所有值从ratt到Rc作为一维数组。
像原始代码中一样，将ratt重塑为6D数组。

代码：

ratt = Rc(2, rti(1:rows(Lr), 1, 1:length(vi), 1:length(vf), 1:length(b), 1:length(h)));
ratt = reshape(ratt, [rows(Lr), 1, length(vi), length(vf), length(b), length(h)]);

测试：为了测试矢量化和非矢量化代码的等同性和速度，我编写了以下代码：

Lr = linspace(100,300,10);
vi = linspace(10,30,10);
vf = linspace(10,30,10);
b = linspace(0.5,1.2,10);
h = linspace(0.3,0.8,10);
Rc = [1000, 1500, 2000, 2500, 3000, 3500;
      29, 22.4, 17.3, 13.4, 10.4, 8];
rti = randi(5, 10, 1, 10, 10, 10, 10);

disp('Non-vectorized:')
tic
for kk = 1:rows(Lr)
  for jj = 1:length(vi)
    for ll = 1:length(vf)
      for mm = 1:length(b)
        for nn = 1:length(h)
          ratt(kk,1,jj,ll,mm,nn) = Rc(2,rti(kk,1,jj,ll,mm,nn));
        endfor
      endfor
    endfor
  endfor
endfor
toc

disp('')

disp('Vectorized:')
tic
ratt1 = Rc(2, rti(1:rows(Lr), 1, 1:length(vi), 1:length(vf), 1:length(b), 1:length(h)));
ratt1 = reshape(ratt1, [rows(Lr), 1, length(vi), length(vf), length(b), length(h)]);
toc

disp('')

if(isequal(ratt,ratt1))
  disp('ratt is equal to ratt1!')
else
  disp('ratt is not equal to ratt1!')
endif

输出：

Non-vectorized:
Elapsed time is 0.16697 seconds.

Vectorized:
Elapsed time is 0.000309944 seconds.

ratt is equal to ratt1!

向量化八度音阶上的多维数组填充

1 个答案: