add eigen solver

Solver/dofManager.h

@@ -513,7 +513,7 @@ class dofManager{
       throw;
     }
   }
-  linearSystem<dataMat> *getLinearSystem(std::string &name)
+  virtual linearSystem<dataMat> *getLinearSystem(std::string &name)
   {
     typename std::map<const std::string, linearSystem<dataMat>*>::iterator it =
       _linearSystems.find(name);

Solver/eigenSolver.cpp

@@ -11,7 +11,7 @@
 #include <slepceps.h>
 
 eigenSolver::eigenSolver(dofManager<double> *manager, std::string A,
-                         std::string B, bool hermitian) 
+                         std::string B, bool hermitian)
   : _A(0), _B(0), _hermitian(hermitian)
 {
   if(A.size()){
@@ -55,7 +55,7 @@ bool eigenSolver::solve(int numEigenValues, std::string which)
   _try(EPSSetDimensions(eps, numEigenValues, PETSC_DECIDE, PETSC_DECIDE));
   _try(EPSSetTolerances(eps, 1.e-7, 20));//1.e-6 50
   //_try(EPSSetType(eps, EPSKRYLOVSCHUR)); //default
-  _try(EPSSetType(eps, EPSARNOLDI)); 
+  _try(EPSSetType(eps, EPSARNOLDI));
   //_try(EPSSetType(eps, EPSARPACK));
   //_try(EPSSetType(eps, EPSPOWER));