Solve bug from inplace substitution in ecldiff2roff

src/subscript/ecldiff2roff/ecldiff2roff.py

@@ -1,11 +1,11 @@
 import argparse
 import logging
-import dateutil
+from typing import List, Set, Tuple, Union
 
+import dateutil.parser
 import xtgeo  # type: ignore
-import subscript
 
-from typing import List, Tuple, Set, Union
+import subscript
 
 logger = subscript.getLogger(__name__)
 
@@ -163,7 +163,7 @@ def ecldiff2roff_main(
     for date_pair in diffdates:
         alldates = alldates.union(set(date_pair))
 
-    ecl_grid = xtgeo.grid3d.Grid().from_file(
+    ecl_grid = xtgeo.grid_from_file(
         eclroot, fformat="eclipserun", restartprops=[prop], restartdates=alldates
     )
     logger.info("Loaded UNRST data at %s dates from %s", len(alldates), eclroot)
@@ -191,8 +191,9 @@ def ecldiff2roff_main(
             str(date_pair[0]),
             str(date_pair[1]),
         )
-        # Inplace substraction, prop1 = prop1 - prop2
-        prop1.values -= prop2.values
+
+        diffprop = prop1.copy()
+        diffprop.values = prop1.values - prop2.values
 
         diffpropname = (
             prop.lower()
@@ -204,7 +205,7 @@ def ecldiff2roff_main(
         filename = outputfilebase + sep + diffpropname + ".roff"
 
         logger.info("Writing to file %s", filename)
-        prop1.to_file(filename, name=diffpropname)
+        diffprop.to_file(filename, name=diffpropname)
 
 
 def main():

tests/test_ecldiff2roff.py

@@ -1,14 +1,14 @@
-import os
 import logging
+import os
 import shutil
 import subprocess
 from pathlib import Path
 
+import numpy as np
 import pytest
-
-from subscript.ecldiff2roff import ecldiff2roff
-
+import xtgeo
 from subscript import getLogger
+from subscript.ecldiff2roff import ecldiff2roff
 
 logger = getLogger("subscript.ecldiff2roff.ecldiff2roff")
 logger.setLevel(logging.INFO)
@@ -170,6 +170,103 @@ def test_mainfunction(
         assert Path(expected_file).exists()
 
 
+def test_values_dateorder(reek_data):
+    """Verify the handling of date order in date pairs, that the
+    sign of values gets correct and it negated when dates are reversed"""
+    ecldiff2roff.ecldiff2roff_main(
+        "2_R001_REEK-0", "PRESSURE", [("20000101", "20000701")]
+    )
+    pressure_diff1 = xtgeo.gridproperty_from_file(
+        "eclgrid--pressure--20000101_20000701.roff"
+    )
+
+    # This tools works such that a reduction in pressure gives a positive value when
+    # the dates "increase". This test assumes that the Reek dataset declines
+    # in pressure:
+    assert pressure_diff1.values.mean() > 0.0
+
+    # Also verify the actual mean value:
+    assert np.isclose(pressure_diff1.values.mean(), 29.6174076)
+
+    # Check that when the dates are reversed, the difference is negated:
+    ecldiff2roff.ecldiff2roff_main(
+        "2_R001_REEK-0", "PRESSURE", [("20000701", "20000101")]
+    )
+    pressure_diff_reverse = xtgeo.gridproperty_from_file(
+        "eclgrid--pressure--20000701_20000101.roff"
+    )
+    assert np.isclose(
+        pressure_diff1.values.mean(), -pressure_diff_reverse.values.mean()
+    )
+
+
+def test_values_samedate(reek_data):
+    """Verify that the same date yields zero change"""
+    ecldiff2roff.ecldiff2roff_main(
+        "2_R001_REEK-0", "PRESSURE", [("20000101", "20000101")]
+    )
+    pressure_diff = xtgeo.gridproperty_from_file(
+        "eclgrid--pressure--20000101_20000101.roff"
+    )
+    assert np.isclose(pressure_diff.values.mean(), 0.0)
+
+
+def test_values_multiple_datepairs(reek_data):
+    """Check that differences for multiple date pairs are handled correctly
+
+    This was a bug in subscript up to v0.12.0"""
+
+    # First establish some thruths:
+    ecldiff2roff.ecldiff2roff_main(
+        "2_R001_REEK-0", "PRESSURE", [("20000101", "20000701")]
+    )
+    pressure_diff1_singlerun = xtgeo.gridproperty_from_file(
+        "eclgrid--pressure--20000101_20000701.roff"
+    )
+    assert np.isclose(pressure_diff1_singlerun.values.mean(), 29.6174076)
+
+    ecldiff2roff.ecldiff2roff_main(
+        "2_R001_REEK-0", "PRESSURE", [("20000701", "20010201")]
+    )
+    pressure_diff2_singlerun = xtgeo.gridproperty_from_file(
+        "eclgrid--pressure--20000701_20010201.roff"
+    )
+    assert np.isclose(pressure_diff2_singlerun.values.mean(), 12.570824)
+
+    ecldiff2roff.ecldiff2roff_main(
+        "2_R001_REEK-0", "PRESSURE", [("20000101", "20010201")]
+    )
+    pressure_diff3_singlerun = xtgeo.gridproperty_from_file(
+        "eclgrid--pressure--20000101_20010201.roff"
+    )
+    assert np.isclose(pressure_diff3_singlerun.values.mean(), 42.18823213)
+
+    # Then run with multiple datepairs:
+    ecldiff2roff.ecldiff2roff_main(
+        "2_R001_REEK-0",
+        "PRESSURE",
+        [("20000101", "20000701"), ("20000701", "20010201"), ("20000101", "20010201")],
+    )
+    pressure_diff1 = xtgeo.gridproperty_from_file(
+        "eclgrid--pressure--20000101_20000701.roff"
+    )
+    pressure_diff2 = xtgeo.gridproperty_from_file(
+        "eclgrid--pressure--20000701_20010201.roff"
+    )
+    pressure_diff3 = xtgeo.gridproperty_from_file(
+        "eclgrid--pressure--20000101_20010201.roff"
+    )
+    assert np.isclose(
+        pressure_diff1.values.mean(), pressure_diff1_singlerun.values.mean()
+    )
+    assert np.isclose(
+        pressure_diff2.values.mean(), pressure_diff2_singlerun.values.mean()
+    )
+    assert np.isclose(
+        pressure_diff3.values.mean(), pressure_diff3_singlerun.values.mean()
+    )
+
+
 def test_errors(reek_data):
     """Test errors from the module"""
     # pylint: disable=unused-argument