Find rows based on set of values/codes

Question

Millie Johnston 2022-9-13

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/1804310-find-rows-based-on-set-of-values-codes

评论： Star Strider 2022-9-14

Hello community,

I have a data set that is 48x14 (called data for this example). Each row has a set of codes (possible codes are 0 1 13 14 15 16 31 42 53 54). a row might look like this: [1 0 0 13 0 0 31 0 0 0 42 0 0 53].

The code is part of a for loop but I am strugglig with one specific part: I want to find rows that have a specific series of codes while ignoing the 0 codes. I thought the following code would work to find rows with the codes 1 13 31 42 and 53 in it:

for i = 1:length(data(:,1))

if all(data(i,find(data(i,:) == [1 13 31 42 53])))

.......

I get the following error:

Arrays have incompatible sizes for this operation.

Any help would be much appreciated!

0 个评论
显示 -2更早的评论隐藏 -2更早的评论

请先登录，再进行评论。

请先登录，再回答此问题。

Answer 1

Star Strider 2022-9-13

0
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/1804310-find-rows-based-on-set-of-values-codes#answer_1052555

在 MATLAB Online 中打开

I am not certain what you want, however the ismember function might be a better option than find for this, especially since everything seems to be integers, so no floating-point approximation problems will be present (requiring ismembertol and likely more coding) —

data =  [1 0 0 13 0 0 31 0 0 0 42 0 0 53];
q = ismember(data, [1 13 31 42 53])
q = 1×14 logical array
   1   0   0   1   0   0   1   0   0   0   1   0   0   1
v = data(q)
v = 1×5
     1    13    31    42    53

Then determine what you want to do with either ‘q’ (using the nnz function could give the number of matches) or ‘v’ (the content of the matches in the vector) here.

.

4 个评论
显示 2更早的评论隐藏 2更早的评论

Millie Johnston 2022-9-14

Excellent! Thank you very much!

Star Strider 2022-9-14

As always, my pleasure!

请先登录，再进行评论。

Answer 2

David Hill 2022-9-13

0
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/1804310-find-rows-based-on-set-of-values-codes#answer_1052540

在 MATLAB Online 中打开

for i = 1:size(data,2) 
   if all(ismember(data(i,:),[0 1 13 31 42 53]))%include 0 

2 个评论
显示无隐藏无

Image Analyst 2022-9-13

This answer doesn't care about the order of the desired sequence of codes you are looking for or if there are any duplicated numbers in the row.

My answer below requires that the sequence match exactly (not be scrambled or in arbitrary order like [13, 53, 42, 31, 1]).

We're not sure which way you want it, but now you have it both ways so you can choose.

Millie Johnston 2022-9-13

I am not looking for the sequnce per say, I am looking for the rows in which those numbers appear together (in any order). Does that make more sense?

请先登录，再进行评论。

Answer 3

Image Analyst 2022-9-13

0
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/1804310-find-rows-based-on-set-of-values-codes#answer_1052550

在 MATLAB Online 中打开

Try this

oneRow =  [1 0 0 13 0 0 31 0 0 0 42 0 0 53];
oneRow(oneRow == 0) = [] % Remove zeros
oneRow = 1×5
     1    13    31    42    53

In addition you should be using isequal

% Define the specific sequence you are looking for.
desiredCodeSequence = [1 13 31 42 53]; % Row should be exactly this.
% See if it matches your zero-removed row.
if isequal(oneRow, desiredCodeSequence)
    % Matched
    fprintf('Matched.\n')
else
    % The row is not the desired sequence.
    fprintf('The row is not the desired sequence.\n')
end
Matched.