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jrkerns · Apr 1, 2024 · b39b820 · b39b820
1 parent 0445666
commit b39b820
Showing 1 changed file with 2 additions and 0 deletions.
diff --git a/pylinac/winston_lutz.py b/pylinac/winston_lutz.py
@@ -1249,6 +1249,8 @@ def bb_shift_vector(self) -> Vector:
                 rotation=img.couch_angle,
             )
             A[2 * idx : 2 * idx + 2, :] = np.array(
+                # note the signs are different than the paper; based on
+                # synthetic data we can prove this. See docs
                 [
                     [-cos(couch), sin(couch), 0],
                     [