Fixing Bug: correct end of circular interpolation

Fixed angle step calculation in circular path generation by dividing by step_num - 1 to ensure proper angular range coverage and avoid over/undersampling

src/pybullet_industrial/interpolation.py

@@ -49,9 +49,12 @@ def build_circular_path(center: np.array, radius: float,
     circular_path = np.zeros((2, step_num))
     for j in range(step_num):
         if clockwise:
-            path_angle = min_angle-j*(max_angle-min_angle)/step_num
+            path_angle = min_angle - j * \
+                (max_angle - min_angle) / (step_num - 1)
         else:
-            path_angle = min_angle+j*(max_angle-min_angle)/step_num
+            path_angle = min_angle + j * \
+                (max_angle - min_angle) / (step_num - 1)
+
         new_position = center + radius * \
             np.array([np.cos(path_angle), np.sin(path_angle)])
         circular_path[:, j] = new_position

tests/test_interpolation.py

@@ -91,8 +91,12 @@ def test_circular_interpolation(self):
             start_point, end_point, radius, samples, axis, clockwise,
             start_orientation, end_orientation)
 
-        # Expected positions for both orientations case (assuming planar interpolation is correct)
-        expected_positions = result_with_both_orientations.positions
+        # Expected positions for both orientations case (using the provided array)
+        expected_positions = np.array([
+            [1.0, 0.61731657, 0.29289322, 0.07612047, 0.0],
+            [0.0, 0.07612047, 0.29289322, 0.61731657, 1.0],
+            [0.0, 0.0, 0.0, 0.0, 0.0]
+        ])
 
         # Generate expected orientations using RotationSpline for SLERP
         start_rot = R.from_quat(start_orientation)