MemoryError in inv(SparseMatrixCSC)

[acroy]

Using inv with a sparse matrix gives

julia> inv(speye(2,2))
ERROR: no method MemoryError(ASCIIString)
 in inv at linalg/sparse.jl:489

since MemoryError doesn't have a string property.
In any case, instead of throwing an exception I would suggest

inv(A::SparseMatrixCSC) = error("The inverse of a sparse matrix can often be dense and can cause the computer to run out of memory. If you are sure you have enough memory, please convert your matrix to a dense matrix.")

IMHO, an MemoryError should only be thrown if it is clear that there will not be enough memory. Here the functionality is simply not implemented, so an error would be more appropriate.

[ivarne]

This will probably be fixed when #4744 gets addressed.

I am sure you can get a Pull Request approved as a temporary fix for this, but if do not want attribution, someone else will definitely do it pretty quickly. Make sure to add a comment about MemoryError, so that it will be found when somebody adds a msg field to MemoryError

[magistere]

Fully agree with @acroy that here error is more appropriate.

[StefanKarpinski]

cc: @ViralBShah