Add: catch division by zero

splinepy/helpme/create.py

@@ -442,6 +442,12 @@ def swept(
 
         # projecting B_(i) onto the plane normal to e1
         B.append(B[i] - _np.dot(B[i], e1) * e1)
+        if _np.linalg.norm(B[i + 1]) < _settings.TOLERANCE:
+            _log.warning(
+                f"Vector B[{i + 1}] is close to zero. Adjusting "
+                f"to avoid division by zero."
+            )
+            B[i + 1] += _settings.TOLERANCE
         B[i + 1] /= _np.linalg.norm(B[i + 1])
 
         # defining e2 and e3 vectors
@@ -478,6 +484,12 @@ def swept(
                 B_rec[i]
                 - _np.dot(B_rec[i], tang_collection[i]) * tang_collection[i]
             )
+            if _np.linalg.norm(B_rec[i + 1]) < _settings.TOLERANCE:
+                _log.warning(
+                    f"Vector B_rec[{i + 1}] is close to zero. Adjusting "
+                    f"to avoid division by zero."
+                )
+                B_rec[i + 1] += _settings.TOLERANCE
             B_rec[i + 1] /= _np.linalg.norm(B_rec[i + 1])
             # middle point between B and B_rec
             B_rec[i + 1] = (B[i + 1] + B_rec[i + 1]) * 0.5