Thanks for your help, I have seen this contrib, but it seems that she don't sort the php array, she display the ezmatrix in her default order, and then she add buttons to sort it with javascript.
I just want to display my matrix in a classic html table, but before looping into, I want to sort it on a column.
As far as I know there is no built in way to sort an ezmatrix. If you know PHP though it is fairly easy to write a template operator that takes an ezmatrix and a column name as input and returns a sorted 2 dimensional array - just grab the values of the matrix, put them into an 2 dimensional array and use e.g. usort() to sort by the specified column.