MATLAB: Matrix problem for same values of column

columnmatrixrepeated valuesrows

A=[29.78         5	 8
   24.97         8	11
   22.98         4	12
   21.05	12	13
   24.78         1	16
   25.53	26	29
   21.43	 2	32
   29.94	11	33
   29.57	15	35
   28.43	17	36
   11.49        23	37
   13.69	37	38
   26.97	28	39
   16.25	25	40
   27.36	36	41
    4.24  	18	42
   19.39	39	44
   29.93	16	45
   25.83	30	46
   26.09	40	47
   27.58	24	48
   28.61	41	49
   29.41	48	50]
and i want 
output =[22.98    4   12
         25.53   26   29
         21.43    2   32
         29.94   11   33
         29.57   15   35
         28.43   17   36
         13.69   37   38
         26.97   28   39
          4.24   18   42
         29.93   16   45
         25.83   30   46
         26.09   40   47
         28.61   41   49
         29.41   48   50 ]
No value in column 2, 3 get repeated and in case of repeated value in any of the column(2,3) the higest value of column 1 is as the output.
For example, in row 1, 2 and 8. column (2,3) have values as
[ 5  8
  8 11
 11 33]
Among these 3 rows row 8, ie. [29.94 11 33] have the highest value so only this row will be the output. all other row like [29.78 5 8] and [24.97 8 11]will be elimanted.
simillarly,
for row 3 = [22.98 4 12]
And 4 = [21.05 12 13]
row 3= [22.98 4 12]
will be output and row 4 will get eliminated.

Best Answer

N = size(A,1);
X = ones(N,1); % group numbers
Z = true(N,1); % logical index
V = 1; % group number
for k = 2:N % for each row...
    Y = A(k,2)==A(1:k-1,3); % check if any matching rows.
    if any(Y)
        X(k) = X(Y); % copy group number (assumed scalar).
        W = X(k)==X(1:k-1); % logical index of that group.
        if all(A(k,1)>A(W,1))
            Z(W) = false; % current val > prev vals.
        else
            Z(k) = false; %  prev val > current val.
        end
    else % no matching rows:
        V = V+1; % increment group number.
        X(k) = V;
    end
end
B = A(Z,:) % output matrix
Giving:
B =
        22.98            4           12
        25.53           26           29
        21.43            2           32
        29.94           11           33
        29.57           15           35
        13.69           37           38
        26.97           28           39
         4.24           18           42
        29.93           16           45
        25.83           30           46
        26.09           40           47
        28.61           41           49
        29.41           48           50
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