find max by groups, subtract the max from values if a certain condition is satisfied

I have a matrix as below (add column name for the convenience here). With the matrix, if max of value for each group is larger than 700, I want to have desired_column = (value - 700) (group 1 and group 3 have larger than 700 for the max(value), since max(value) are 1300 and 900 respectively). However, I do not want to subtract 700 when outside is 1.

group  outside  value desired_column
1  0  1300
1  0  800
1  1  0
2  0  150
2  0  600
2  1  0
3  0  800
3  0  900
3  1  0

Here is what I want to have

1  0  1300  600
1  0  800  100
1  1  0  0
2  0  150  150
2  0  600  600
2  1  0  0
3  0  800  100
3  0  900  200
3  1  0  0

Answer 1

[Ameer Hamza]

This will process the matrix as specified in question

partition = splitapply(@(x) {x}, A, A(:, 1));

for i = 1:length(partition)
  partition{i}(index, 4) = partition{i}(index, 3);
  index = max(partition{i}(:,3)) > 700 & partition{i}(:,2)~=1;
  partition{i}(index, 4) = partition{i}(index, 3) - 700;
end

cell2mat(partition);