simple question on passing matrix arguments to functions

[John Boik]

Hello.  I have another simple question for the group.  There are no examples
in the gsl manual (that I could find) of passing a matrix or vector to a
function.  If you create a matrix, say M, in main(), how do you pass it on
to newfunction()?  I assume you pass the pointer as *M, but that does not
seem to work for me.  In the new function, calls to gsl_matrix_get(M,i,j)
give me an error on compilation.  Do you need to use a gsl_matrix_view_array
command to remake the matrix in newfunction()?

Thanks,
John