MATLAB: Group an array according a condition

Question

Hi everyone

i have an array like this

A= 
   2   10    10.1  12   14   110
   2   10.1  11    12   15   145
   3   12    12    12   24   223
   3   12    11.4  11   23   100
   3   10    12    20   18   211
   4   9     23    11   11   98

I want to create a new B array where i get the maximum value of each column according to the first column value

B=
  2   10.1   11   12    15    145
  3   12     12   20    24    223
  4   9      23   11    11    98

i don´t want to use loops. is there a way to do it by using just matlab functions?

thanks in advance

Answer 1

B_table = varfun(@max,array2table(A),'GroupingVariables','A1')

or

B = splitapply(@(x)max(x,[],1),A,findgroups(A(:,1)));

or

g = findgroups(A(:,1)); % or >> [~,~,g] = unique(A(:,1))
[ii,jj] = ndgrid(g,1:size(A,2));
B = accumarray([ii(:),jj(:)],A(:),[],@max);