How find the row number for different elements in a column?

Suppose I set a condition where I choose only a certain element from each column. Now how will I get the row number corresponding to each element I have selected from each column. Note that the result should be an array with n elements, where n= number of columns.

Answer 1

[Matt J]

As an example, suppose you wanted to find the first occurrence of a 2 in each column. Then one way would be,

A=randi(10,10,5)

A = 10×5

6 8 9 6 2 9 9 2 5 10 4 7 2 5 10 5 5 9 3 1 8 1 8 7 7 6 3 4 1 2 5 2 7 10 10 2 3 8 1 9 3 9 8 9 7 1 2 3 7 4

[~,firstInstance]=max(A==2)

firstInstance = 1×5

8 7 2 1 1