Question

我目前有两个时间轴（timeline1和timeline2），带有匹配的数据（data1和data2）。时间表差不多，但不太匹配（大约90％的常见值）。

我正在尝试从data1和data2中找到对应于相同时间戳的值（忽略所有其他值）

我的第一个简单实现如下（鉴于我的时间轴包含数千个值，显然非常慢）。关于如何改进这个的任何想法？我确信有一种聪明的方法可以避免for循环或查找操作......

% We expect the common timeline to contain
% 0 1 4 5 9
timeline1 = [0 1 4 5 7 8 9 10];
timeline2 = [0 1 2 4 5 6 9];

% Some bogus data
data1 = timeline1*10;
data2 = timeline2*20;

reconstructedData1 = data1;
reconstructedData2 = zeros(size(data1));

currentSearchPosition = 1;

for t = 1:length(timeline1)
   % We only look beyond the previous matching location, to speed up find
   matchingIndex = find(timeline2(currentSearchPosition:end) == timeline1(t), 1);

   if isempty(matchingIndex)
      reconstructedData1(t) = nan;
      reconstructedData2(t) = nan;
   else
      reconstructedData2(t) = data2(matchingIndex+currentSearchPosition-1);
      currentSearchPosition = currentSearchPosition+matchingIndex;
   end   

end

% Remove values from data1 for which no match was found in data2
reconstructedData1(isnan(reconstructedData1)) = [];
reconstructedData2(isnan(reconstructedData2)) = [];

Answer 1

您可以使用Matlab的intersect函数：

c = intersect(A, B)

Answer 2

你不能打电话给INTERSECT吗？

commonTimeline = intersect(timeline1,timeline2);
commonTimeline =
     0     1     4     5     9

Answer 3

您需要使用从intersect返回的索引。

[~ ia ib] = intersect(timeline1, timeline2);
recondata1 = data1(ia);
recondata2 = data2(ib);

如何在Matlab中优化此时间轴匹配代码？

3 个答案: