How to find column where 0 turns to 1 for each row

1 次查看（过去 30 天）
Tanika Bawa
Tanika Bawa 2022-7-14
编辑： Bruno Luong 2022-7-15
Hello!
I would like to be able to find the column (or column title) for each row where the 0 turns to 1.
I have attached example rows (egcolumnsep.mat), so for example for row 5, I would like it to return column 20 (or Bins_11). I would like an output for all the rows though. Some rows might have only 0's (this can be NaN). This basically gives me the reaction time for each row.
Thank you for your help! =)

请先登录，再回答此问题。

采纳的回答

Bruno Luong
Bruno Luong 2022-7-15
编辑：Bruno Luong 2022-7-15
Ran in:
load('egcolumnsep.mat');
c1 = find(strcmp(DATAb1.Properties.VariableNames,'Bins_1')); % == 10
% Extract relevant data
A = table2array(DATAb1(:,c1:end));
if ~all(ismember(A,[0 1]),'all')
error('Data must be 0 or 1')
end
[cols,rows] = find(diff(A.')==1);
cols = cols+c1;
Idx01 = table(rows,cols)
Idx01 = 37×2 table
rows cols ____ ____ 1 468 1 499 1 855 1 890 2 196 3 452 3 487 3 531 3 828 3 860 4 306 4 338 4 370 4 404 4 434 4 468
  2 个评论
Tanika Bawa
Tanika Bawa 2022-7-15
Thank you! Do you know how I could get it so that I only get ther first transition from 0 to 1?
Bruno Luong
Bruno Luong 2022-7-15
编辑：Bruno Luong 2022-7-15
Ran in:
Why didn't tell us that you are interested only the first transition in the question?
You can call this statement after the above scriot
groupsummary(Idx01, 'rows','min')
or start from scratch
load('egcolumnsep.mat');
c1 = find(strcmp(DATAb1.Properties.VariableNames,'Bins_1')); % == 10
% Extract relevant data
A = table2array(DATAb1(:,c1:end));
if ~all(ismember(A,[0 1]),'all')
error('Data must be 0 or 1')
end
[a,cols] = max(A,[],2);
cols = (cols+c1-1) .* (a==1) % returns 0 if no transition 0->1 is found
cols = 5×1
468 196 452 306 20

请先登录，再进行评论。

更多回答（1 个）

Jonas
Jonas 2022-7-14
编辑：Jonas 2022-7-14
Ran in:
yourMat=[0 0 0 0 0;
0 1 1 0 0;
0 0 0 1 0];
where=arrayfun(@(idx)find(diff(yourMat(idx,:))==1,1,'first')+1,1:size(yourMat,1),'UniformOutput',false)'
where = 3×1 cell array
{1×0 double} {[ 2]} {[ 4]}
an empty cell shows that there was not such a change
you could set it to NaN and convert to an normal array by
where{cellfun('isempty',where)}=NaN
where = 3×1 cell array
{[NaN]} {[ 2]} {[ 4]}
where=cell2mat(where)
where = 3×1
NaN 2 4
  3 个评论
显示 1更早的评论
Jonas
Jonas 2022-7-14
you can convert your table to a matrix before, e.g. yourTable{:,:} or table2array()
Tanika Bawa
Tanika Bawa 2022-7-14
I did try that and it doesn't really let me do it unfortunately. It gives me this error:
"Unable to concatenate the specified table variables.
Caused by:
Error using categorical/cat (line 56)
Unable to concatenate a double array and a categorical array."
I do need to keep all the columns (because in the end I just want to add a column at the end with the results from this)

请先登录，再进行评论。

类别

在 Help Center 和 File Exchange 中查找有关 Matrices and Arrays 的更多信息

标签

产品


版本

R2020b

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by