added a new method to assign matrix values, which also avoids a (potentialy costly) initialization of the matrix sparsity.
shorter, better code that is shared among the classes. bug fix in zerorow, greater robustness in compression/uncompression of the sparse matrix.
added a working, extremely innefficient dlib-based solver (could be better, but what the heck.
works and looks better now (win-win).
works, looks better and is even simpler now (win-win-win).
improved the working of options, though i cant stop it from calling exit when a singular matrix is found. call Intel, not me.
looks better, but is not any better than before.
conforming changes to base class (neither solver is working at all yet_.
addd commented code that might work better than the currnt one
optimization: only insert transposed pair in coo. matrix when intended pair is also inserted
sumrows does not require matrix uncompression
linearsystem has a optional sparsity pattern instead of initialization value (which was not respected anyway for sparse matrices)
related changes to previous commit
some fixes to matrix initialization/clearing, bugfix in assigning from vector of size 1, improved compression and ensure_structural_symmetry, and added a direct (row-oriented only) compression initialization from sparsity pattern (based on old code, but works very well)
Merge pull request #17 from pmaciel/master

works very well with muphys, when respective branch is merged