Fix gl333

saqc/funcs/resampling.py

@@ -14,7 +14,7 @@ from typing_extensions import Literal
 import numpy as np
 import pandas as pd
 
-from dios import DictOfSeries
+from dios import DictOfSeries, DtItype
 
 from saqc.constants import *
 from saqc.core import register, Flags
@@ -331,6 +331,11 @@ def resample(
     """
 
     datcol = data[field]
+
+    # workaround for #GL-333
+    if datcol.empty and data.itype in [None, DtItype]:
+        datcol = pd.Series(index=pd.DatetimeIndex([]), dtype=datcol.dtype)
+
     freq = evalFreqStr(freq, freq_check, datcol.index)
 
     datcol = aggregate2Freq(

tests/funcs/test_proc_functions.py

@@ -10,6 +10,8 @@
 # see test/functs/fixtures.py for global fixtures "course_..."
 import pytest
 
+import pandas as pd
+import saqc
 import dios
 
 from saqc.constants import *
@@ -141,3 +143,9 @@ def test_offsetCorrecture():
     flags = initFlagsLike(data)
     data, _ = correctOffset(data, "dat", flags, 40, 20, "3d", 1)
     assert (data == 0).all()[0]
+
+
+# GL-333
+def test_resampleSingleEmptySeries():
+    qc = saqc.SaQC(pd.DataFrame(1, columns=["a"], index=pd.DatetimeIndex([])))
+    qc.resample("a", freq="1d")