I recently upgraded from Compser XE 2013SP1U3 to Composer XE 2016U3, and thus from MKL 11.1.3 to MKL 11.3.3. This has caused a slightly changed behavior in the output from Pardiso in the following situations:
- When trying to "solve" a system of equations of dimension 0 (I have a set of unit tests which for one test degenerates to this case).
- 11.1.3: the error code is 0 (no error), so that the solution may be interpreted as the empty vector.
- 11.3.3: the error code is -1, indicating "inconsistent input."
- When trying to solve a system Ax=b in which A is an 5x5 matrix of all zeros, and b is a 5x1 matrix of all zeros.
- 11.1.3: the error code is -7
- 11.3.3: the error code is -4
Are these changes expected?
Of course, both cases are degenerate and not of any practical interest. I just need to confirm that this changed behavior does not suggest any errors in my (other) input to Pardiso.