SF: bugfix for avg operation with group mode

The avg operation in group mode does a wavenote and meta data transfer.
This transfer works only if the number of datasets in the output waves
are equal to the number of datasets of the input waves.
(If there would be less input than output waves, there would be no data
for some output waves)

The group mode did transfer always from the first group.
If the first group contained less datasets than the group with the greatest
number of datasets then the transfer failed.

As the result of the group averaging always has the same number of datasets
as the greatest group the wave note and meta data transfer is now done from
the greatest input group.

Since:
272c26b (SF: operation avg add mode to average over groups of data, 2025-11-12)

Author: MichaelHuth

Packages/MIES/MIES_SweepFormula_Operations.ipf

@@ -517,7 +517,6 @@ Function/WAVE SFO_OperationAvg(STRUCT SF_ExecutionData &exd)
 	elseif(!CmpStr(mode, SF_OP_AVG_GROUPS))
 		WAVE/WAVE dataFromEachGroup = SFH_GetDatasetArrayAsResolvedWaverefs(exd, 0, resolveSelect = 1)
 		WAVE/WAVE averagedGroup     = SFO_OperationAvgImplSweepGroups(dataFromEachGroup, exd.graph, opShort)
-		SFH_TransferFormulaDataWaveNoteAndMeta(dataFromEachGroup[0], averagedGroup, opShort, SF_DATATYPE_AVG)
 
 		return SFH_GetOutputForExecutor(averagedGroup, exd.graph, opShort)
 	else
@@ -527,15 +526,17 @@ End
 
 static Function/WAVE SFO_OperationAvgImplSweepGroups(WAVE/WAVE sweepsFromEachSelection, string graph, string opShort)
 
-	variable numData, numMaxSweeps, numGroups, i, j
+	variable numData, numMaxSweeps, numGroups, i, j, maxIdx
 	STRUCT RGBColor s
 
 	[s] = GetTraceColorForAverage()
 	Make/FREE/W/U traceColor = {s.red, s.green, s.blue}
 
 	numGroups = DimSize(sweepsFromEachSelection, ROWS)
 	Make/FREE/D/N=(numGroups) sweepCnts = DimSize(sweepsFromEachSelection[p], ROWS)
-	numMaxSweeps = WaveMax(sweepCnts)
+	WaveStats/Q/M=1 sweepCnts
+	numMaxSweeps = V_max
+	maxIdx       = V_maxRowLoc
 	WAVE/WAVE output = SFH_CreateSFRefWave(graph, opShort, numMaxSweeps)
 	for(i = 0; i < numMaxSweeps; i += 1)
 		Make/FREE/WAVE/N=(numGroups) avgSet
@@ -553,6 +554,7 @@ static Function/WAVE SFO_OperationAvgImplSweepGroups(WAVE/WAVE sweepsFromEachSel
 		JWN_SetNumberInWaveNote(output[i], SF_META_TRACETOFRONT, 1)
 		JWN_SetNumberInWaveNote(output[i], SF_META_LINESTYLE, 0)
 	endfor
+	SFH_TransferFormulaDataWaveNoteAndMeta(sweepsFromEachSelection[maxIdx], output, opShort, SF_DATATYPE_AVG)
 
 	return output
 End