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2.58 find first value in column larger than some value and cut matrix from there

Given matrix \[ \left ( {\begin {array}{ccc} 1 & 5 \\ 2 & 3 \\ 4 & 8 \\ 7 & 2 \end {array}} \right ) \]

search in column 2 of matrix for the first time a value exceeds 6 and return the matrix up to that row. The result should be

\[ \left ( {\begin {array}{ccc} 1 & 5 \\ 2 & 3 \end {array}} \right ) \]

Mathematica 

a = {{1, 5}, {2, 3}, {4, 8}, {7, 2}}; 
Min@Position[a, {x_, y_} /; y > 6] 
(* 3 *) 
 
a[[1 ;; % - 1]]
 


{{1, 5}, {2, 3}}

 

Matlab 

A = [1,5;2,3;4,8;7,2]; 
A(1:find(A(:,2)>6)-1,:)
 


ans = 
      1     5 
      2     3

 

Maple 

A:=Matrix([[1,5],[2,3],[4,8],[7,2]]); 
idx := ListTools:-SelectFirst(1, x->x>6 , A[..,2],output=indices); 
if idx[1]>1 then 
   A[1..idx[1]-1,..]; 
else 
   A[1..idx[1],..]; 
fi;

\[ \left [\begin {array}{cc} 1 & 5 \\ 2 & 3 \end {array}\right ] \]

 

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