Merge pull request #37708 from mantidproject/assert-almost-equal

Added kwargs to pass parameters to Compare Workspaces function.

Author: KedoKudo

Framework/PythonInterface/mantid/_testing/AssertAlmostEqual.py

@@ -6,9 +6,10 @@
 # SPDX - License - Identifier: GPL - 3.0 +
 
 from mantid.simpleapi import CompareWorkspaces
+from mantid.kernel import Property
 
 
-def assert_almost_equal(Workspace1, Workspace2, rtol=0.0, atol=0.0):
+def assert_almost_equal(Workspace1, Workspace2, rtol=Property.EMPTY_DBL, atol=Property.EMPTY_DBL, **kwargs):
     """
     Raises an assertion error if two workspaces are not within specified tolerance.
 
@@ -26,23 +27,26 @@ def assert_almost_equal(Workspace1, Workspace2, rtol=0.0, atol=0.0):
     AssertionError
         If Workspace1 and Workspace2 are not equal up to specified precision
     ValueError
-        If atol and rtol are both provided
+        If atol and rtol are both not provided
 
     """
-
-    if rtol != 0.0 and atol != 0.0:
-        raise ValueError("Specify rtol or atol, not both")
-    _rel = False
-    tolerance = 1e-10
-    if atol:
-        tolerance = atol
-
-    if rtol:
-        tolerance = rtol
-        _rel = True
-
-    result, message = CompareWorkspaces(Workspace1, Workspace2, Tolerance=tolerance, ToleranceRelErr=_rel)
-    msg_dict = message.toDict()
-    if not result:
-        msg = ", ".join(msg_dict["Message"]) + f", Workspaces are not within tolerance ({tolerance})"
-        raise AssertionError(msg)
+    # check arguments
+    if len(set(kwargs.keys()).intersection({"Workspace1", "Workspace2", "Tolerance", "ToleranceRelErr"})):
+        raise ValueError("Workspace1, Workspace2, Tolerance, ToleranceRelErr cannot be passed as additional parameters")
+
+    if rtol == Property.EMPTY_DBL and atol == Property.EMPTY_DBL:
+        raise ValueError("Specify rtol or atol")
+
+    if rtol > Property.EMPTY_DBL:
+        result, message = CompareWorkspaces(Workspace1, Workspace2, Tolerance=rtol, ToleranceRelErr=True, **kwargs)
+        msg_dict = message.toDict()
+        if not result:
+            msg = ", ".join(msg_dict["Message"]) + f", Workspaces are not within relative tolerance ({rtol})"
+            raise AssertionError(msg)
+
+    if atol > Property.EMPTY_DBL:
+        result, message = CompareWorkspaces(Workspace1, Workspace2, Tolerance=atol, ToleranceRelErr=False, **kwargs)
+        msg_dict = message.toDict()
+        if not result:
+            msg = ", ".join(msg_dict["Message"]) + f", Workspaces are not within absolute tolerance ({atol})"
+            raise AssertionError(msg)

Framework/PythonInterface/test/python/mantid/_testing/AssertAlmostEqualTest.py

@@ -22,7 +22,7 @@ def setUpClass(self):
         self.ws3 = ws3
 
     def test_simple(self):
-        assert_almost_equal(self.ws1, self.ws1)
+        assert_almost_equal(self.ws1, self.ws2, atol=1, rtol=1)
 
     def test_atol(self):
         # compare (ws1 - ws2) < atol
@@ -33,11 +33,8 @@ def test_rtol(self):
         assert_almost_equal(self.ws1, self.ws3, rtol=0.7)
 
     def test_raises(self):
-        with self.assertRaises(AssertionError):
-            assert_almost_equal(self.ws1, self.ws2)
-
         with self.assertRaises(ValueError):
-            assert_almost_equal(self.ws1, self.ws2, atol=1, rtol=1)
+            assert_almost_equal(self.ws1, self.ws2)
 
 
 if __name__ == "__main__":

docs/source/api/python/mantid/testing/assert_almost_equal.rst

@@ -4,7 +4,12 @@
  assert_almost_equal
 =====================
 
-This is a Python function for testing if two modules are within a tolerance
+This is a Python function for testing if two modules are within a tolerance.
+At least ``rtol`` or ``atol`` parameters should be specified. Neither being
+specified generates a ``ValueError`` exception. Both being specified runs
+the underlying :ref:`algm-CompareWorkspaces` algorithm
+twice, with relative tolerance being first.
+
 
 
 .. module:`mantid.testing`

docs/source/release/v6.11.0/Framework/Python/New_features/37708.rst

@@ -0,0 +1 @@
+- The python function ``assert_almost_equal`` for testing if two modules are within a tolerance was reworked