Finding multiple minimum number in a column and location

Hello, I have a matrix X =

   100    14    10     4    10     6
   101     2     8     8    12    18
   102     8     4     8    18    14
   103     2    12     8     8    18
   104     5    15     5     5    15
   105     8    16     6     4    12
   106     7    11     3     9    13
   107    16    12     6     8     4
   108    12    10     2    10     8
   109     6     6     4    14    14

For second column, 2. and 4. rows are 2 and they are the smallest number.. If there is more then one same smallest number how can I find all of them location?

Answer 1

[madhan ravi]

a=[   100    14    10     4    10     6
   101     2     8     8    12    18
   102     8     4     8    18    14
   103     2    12     8     8    18
   104     5    15     5     5    15
   105     8    16     6     4    12
   106     7    11     3     9    13
   107    16    12     6     8     4
   108    12    10     2    10     8
   109     6     6     4    14    14]
id=(min(a))

[idy,idx]=find(ismember(a,id))

location = [idx idy] %idx represent row number and idk column number

[Ali Aygün]

It doesnt work, I need to find minimum number of every column and location... however, second column has 2 minimum number so I should find 2 location for that one

[madhan ravi]

see edited , each row in location represents position of minimum of each column

[Bruno Luong]

still doesn't work, test with

a = [1 10;
     10 20]

It will return the position of lower-left 10, which is not wanted.

Answer 2

[Bruno Luong]

   X = [...
     100    14    10     4    10     6
     101     2     8     8    12    18
     102     8     4     8    18    14
     103     2    12     8     8    18
     104     5    15     5     5    15
     105     8    16     6     4    12
     106     7    11     3     9    13
     107    16    12     6     8     4
     108    12    10     2    10     8
     109     6     6     4    14    14]

[row,col] = find(X == min(X,[],1));
position = [row,col]

>>

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