docs: def check_orthogonal(angle):
          """Check the given Dinf angle based on D8 flow direction encoding code by ArcGIS"""
          flow_dir_taudem = -1
          flow_dir = -1
          if MathClass.floatequal(angle, FlowModelConst.e):
              flow_dir_taudem = FlowModelConst.e
              flow_dir = 1
          elif MathClass.floatequal(angle, FlowModelConst.ne):
              flow_dir_taudem = FlowModelConst.ne
              flow_dir = 128
          elif MathClass.floatequal(angle, FlowModelConst.n):
              flow_dir_taudem = FlowModelConst.n
              flow_dir = 64
          elif MathClass.floatequal(angle, FlowModelConst.nw):
              flow_dir_taudem = FlowModelConst.nw
              flow_dir = 32
          elif MathClass.floatequal(angle, FlowModelConst.w):
              flow_dir_taudem = FlowModelConst.w
              flow_dir = 16
          elif MathClass.floatequal(angle, FlowModelConst.sw):
              flow_dir_taudem = FlowModelConst.sw
              flow_dir = 8
          elif MathClass.floatequal(angle, FlowModelConst.s):
              flow_dir_taudem = FlowModelConst.s
              flow_dir = 4
          elif MathClass.floatequal(angle, FlowModelConst.se):
              flow_dir_taudem = FlowModelConst.se
              flow_dir = 2
          return flow_dir_taudem, flow_dir