Hi, I need to create a rectangular matrix which takes vector structured by a DMDA and transforms them to vectors structured with an other DMDA. It does not look like there is a routine to do this since apparently DMCreateMatrix assumes square matrix. What is the clean way to do this ?
The problem is I have a DMDA with 8 degrees of freedom (dof) and my matrix sends vectors living in a subspace with 3 dof to the other 5 dof subspace. I can define a square matrix living in the large, 8 dof subspace, but this is of course very inefficient in terms of memory and time. Thanks Best Timothée
