Sometimes, you would need to check the data stream session in your code. you can use the following

using elsystem; 
 
variables: 
	int Index( 0 ), 
	DataStream DS( NULL ), 
	float Flt(0); 
 
Once 
Begin 
	ClearPrintLog(); 
	Print("Count: ",  AnalysisTechnique.datastreams.Count:0:0); 
	 
	for Index = 0 to analysistechnique.datastreams.Count - 1 
	begin 
		DS = analysistechnique.datastreams.Stream[Index]; 
		print(index:0:0, " ", DS.DataNum:0:0, " ", DS.SessionName); 
	end; 
	 
	 
	DS = AnalysisTechnique.DataStreams.DefaultStream; 
	Print("Default DataNum=", DS.DataNum, " TimeZone=", DS.timeZone.ToString()); 
	 
	DS = AnalysisTechnique.DataStreams[0];	 
	Print("DataStreams[0]=", DS.DataNum); 
	 
	DS = AnalysisTechnique.DataStreams.StreamFromDataNum[0];	 
	Print("StreamFromDataNum[0]=", DS.DataNum); 
end;

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