Determine identical value of a column

1 view (last 30 days)
Kim Lopez
Kim Lopez on 18 Oct 2017
Commented: KL on 18 Oct 2017
Supposed i have this table, values in row 2 and row 3 in column1 are identical, same also at row 6 and row 7. Is there a way I can determine those values and add and store the values and then remove one identical value?
11 0.9
8 0.3
8 0.7
6 0.2
5 2.3
3 4.6
3 6.1
0 8.7
the output table would look like this
11 0.9
8 0.10
6 0.2
5 2.3
3 10.7
0 8.7

Accepted Answer

KL
KL on 18 Oct 2017
Edited: KL on 18 Oct 2017
You could use findgroups and splitapply
data = [11 0.9
8 0.3
8 0.7
6 0.2
5 2.3
3 4.6
3 6.1
0 8.7];
grps = findgroups(data(:,1)); %find groups here
grp_sum = splitapply(@sum,data(:,2),grps); %apply sum on these groups
res = [unique(data(:,1)) grp_sum] %summarize the result
note that the resultant array is sorted and also you'd need 2015b or later.
For older versions, use a table maybe,
t = array2table(data);
g = varfun(@sum, t, 'GroupingVariable','data1')
  4 Comments
Kim Lopez
Kim Lopez on 18 Oct 2017
By the way, is this also working on cells?
KL
KL on 18 Oct 2017
Probably you will have to superimpose it with a cellfun in that case. I'd prefer a table for such data manipulation.

Sign in to comment.

More Answers (0)

Categories

Find more on Numeric Types in Help Center and File Exchange

Community Treasure Hunt

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

Start Hunting!