fix solver tol in dir name in mesh studies

LDDsimulation/LDDsimulation.py

@@ -1563,7 +1563,7 @@ class LDDsimulation(object):
         # if we want to investigate the EOC and mesh dependence, we do not want
         # to put all data files with different grids in different directories.
         if self.mesh_study:
-            dirname = "dt" + "{}".format(self.timestep_size)+ "solver_tol{}".format(self.LDDsolver_tol) + "mesh_study_t0-{}".format(self.starttime) + gravity_string + "/"
+            dirname = "dt" + "{}".format(self.timestep_size)+ "mesh_study_on-[{1:.2f},{1:.2f}]".format(self.starttime,self.endtime) + gravity_string + "/"
         else:
             dirname = "mesh_res" + "{}_".format(self.mesh_resolution)\
                   + "dt" + "{}".format(self.timestep_size)\