On 02/04/2020 03:54 PM, Bill Greene
wrote:

What is an "N-D array"? Do you mean 3 or more
dimensions?

Yes, that is the general usage of N-D array in Octave documentation.

As far as I am aware, the Mass matrix must be a 2-D full or
sparse matrix.

Okay. Is the matrix also required to be real and square?

Thanks,

Rik

The
ode solver options "Mass" and "Jacobian" can be either a
function

handle or a matrix according to odeset(). If it is a matrix,
does that

mean a numeric 2-D matrix or just a numeric N-D array?

The input validation for ode15i and ode15s has to be re-done
because of a

change in the behavior of str2func, and I'm taking the
opportunity to

improve it.

Thanks,

Rik