转换 MatLab 代码 - 困惑

Converting MatLab code - Confused

本文关键字:困惑 代码 MatLab 转换      更新时间:2023-10-16

基本上,我有最后一段代码可以从MatLab转换为C++。

该函数接收 2D 向量,然后根据 2 个条件检查 2D 向量的元素,如果不匹配,它将删除块。但是我对 MatLab 中的代码想要返回什么感到困惑,是 2D 还是 1D 向量?这是代码:

function f = strip(blocks, sumthresh, zerocrossthresh)
% This function removes leading and trailing blocks that do 
% not contain sufficient energy or frequency to warrent consideration.
% Total energy is measured by summing the entire vector.
% Frequency is measured by counting the number of times 0 is crossed.
% The parameters sumthresh and zerocrossthrech are the thresholds,
% averaged across each sample, above which consideration is warrented.
% A good sumthresh would be 0.035
% A good zerocrossthresh would be 0.060
len = length(blocks);
n = sum(size(blocks)) - len;
min = n+1;
max = 0;
sumthreshtotal = len * sumthresh;
zerocrossthreshtotal = len * zerocrossthresh;
for i = 1:n
currsum = sum(abs(blocks(i,1:len)));
currzerocross = zerocross(blocks(i,1:len));
if or((currsum > sumthreshtotal),(currzerocross > zerocrossthreshtotal))
if i < min
  min = i;
end
if i > max;
  max = i;
  end
end
end
% Uncomment these lines to see the min and max selected
% max
% min
 if max > min
   f = blocks(min:max,1:len);
 else
 f = zeros(0,0);
end

或者,与其返回另一个向量(无论是 1D 还是 2D),不如实际发送向量的内存位置并从中删除块?所以例如..

for(unsigned i=0; (i < theBlocks.size()); i++)
{
  for(unsigned j=0; (j < theBlocks[i].size()); j++)
  {
      // handle theBlocks[i][kj] .... 
  }
}

另外,我不明白这行:

currsum = sum(abs(blocks(i,1:len)));

基本上:(i,1:len)

有什么想法吗?谢谢:)

blocks(i,1:len)告诉数组它想要从blocks[i][1 to the end] .因此,如果它是一个 3x3 数组,它会执行以下操作:

blocks[i][1]
blocks[i][2]
blocks[i][3]
.
.
.
blocks[i][end]

然后,它获取矩阵内容的绝对值并将它们加在一起。它返回一个 [x][x] 矩阵,但长度要么是 0x0,要么是 (max)X(len)。