docs: def dropanalysis(np, fel, p, ad8, ssa, outlet, minthresh, maxthresh, numthresh,
                       logspace, drp, workingdir=None,
                       mpiexedir=None, exedir=None, log_file=None, runtime_file=None, hostfile=None):
          """Drop analysis for optimal threshold for extracting stream."""
          parstr = '%f %f %f' % (minthresh, maxthresh, numthresh)
          if logspace == 'false':
              parstr += ' 1'
          else:
              parstr += ' 0'
          fname = TauDEM.func_name('dropanalysis')
          return TauDEM.run(FileClass.get_executable_fullpath(fname, exedir),
                            {'-fel': fel, '-p': p, '-ad8': ad8, '-ssa': ssa, '-o': outlet},
                            workingdir,
                            {'-par': parstr},
                            {'-drp': drp},
                            {'mpipath': mpiexedir, 'hostfile': hostfile, 'n': np},
                            {'logfile': log_file, 'runtimefile': runtime_file})