Switched back to returning boolean from XRotor.operate, and expose rms as property instead.

Author: danieldevriesdarcorp

setup.py

@@ -24,7 +24,7 @@
 from setuptools.extension import Extension
 from setuptools.command.build_ext import build_ext
 
-version = '0.0.8'
+version = '0.0.9'
 
 options = {k: 'OFF' for k in ['--opt', '--debug', '--cuda']}
 for flag in options.keys():

src/fortran/interface.f90

@@ -125,6 +125,11 @@ subroutine save_prop() bind(c, name='save_prop')
         call save(ctxt, 'output.prop')
     end subroutine save_prop
 
+    function get_rms() bind(c, name='get_rms')
+        real(c_float) :: get_rms
+        get_rms = ctxt%rms
+    end function get_rms
+
     subroutine get_performance(rpm, thrust, torque, power, efficiency) bind(c, name='get_performance')
         real(c_float), intent(out) :: rpm, thrust, torque, power, efficiency
 

src/xrotor/test.py

@@ -94,12 +94,13 @@ def test_solve_for_rpm(self):
         """
         xr = XRotor()
         xr.case = Case.from_dict(case)
-        rms = xr.operate(1, 2000)
+        conv = xr.operate(1, 2000)
         perf = xr.performance
 
         print_perf(perf)
 
-        self.assertTrue(rms < 1.0e-7)
+        self.assertTrue(conv)
+        self.assertTrue(xr.rms < 1.0e-7)
         self.assertAlmostEqual(perf.rpm, 2000, 0)
         self.assertAlmostEqual(perf.thrust, 481, 0)
         self.assertAlmostEqual(perf.torque, 105, 0)
@@ -117,12 +118,13 @@ def test_solve_for_thrust(self):
         """
         xr = XRotor()
         xr.case = Case.from_dict(case)
-        rms = xr.operate(2, 500)
+        conv = xr.operate(2, 500)
         perf = xr.performance
 
         print_perf(perf)
 
-        self.assertTrue(rms < 1.0e-7)
+        self.assertTrue(conv)
+        self.assertTrue(xr.rms < 1.0e-7)
         self.assertAlmostEqual(perf.rpm, 2019, 0)
         self.assertAlmostEqual(perf.thrust, 500, 0)
         self.assertAlmostEqual(perf.torque, 107, 0)

src/xrotor/xrotor.py

@@ -50,7 +50,8 @@ def __init__(self):
         self._lib = cdll.LoadLibrary(self._lib_path)
 
         self._lib.get_print.restype = c_bool
-        self._lib.operate.restype = c_float
+        self._lib.operate.restype = c_bool
+        self._lib.get_rms.restype = c_float
 
         self._lib.init()
         self._case: Case = None
@@ -121,6 +122,11 @@ def station_conditions(self):
         self._lib.get_station_conditions(byref(c_int(n)), xi.ctypes.data_as(fptr), re.ctypes.data_as(fptr))
         return xi, re
 
+    @property
+    def rms(self):
+        """float: The root-mean-squared error of the last XRotor analysis."""
+        return float(self._lib.get_rms())
+
     def operate(self, specify, value):
         """Operate the propeller at a specified RPM or thrust.
 
@@ -133,10 +139,10 @@ def operate(self, specify, value):
 
         Returns
         -------
-        rms : float
-            Root-mean-squared error of XRotor's convergence. XRotor considers itself converged if rms < 1.0e-7.
+        conv : bool
+            True is XRotor converged.
         """
-        return float(self._lib.operate(byref(c_int(specify)), byref(c_float(value))))
+        return self._lib.operate(byref(c_int(specify)), byref(c_float(value)))
 
     def print_case(self):
         """Print the characteristics of the run case at the last operating point to the terminal."""