MATLAB: Determine identical value of a column

identical column

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

Best Answer

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')
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