Hi everybody, I'm trying to split an Einstein Analytics dataset into different date groups, and then append the columns to one another.I'd like to assign a certain date range to one variable, the previous week to a second variable, and then cogroup the two by day number. I've attached a sample of what I'm able to achieve with a "union" function, however my goal would be to join the "Data_Re.Day_Week_Num" columns to bring this information on the same line. 

Here's my attempt at using a cogroup to join the two, however I get an ID TOKEN error in my last "foreach" when trying to refer to either column in q2 or q3.
q= 'DateSource;
q2 = filter q by date('Disposition_Time__c_Year', 'Disposition_Time__c_Month', 'Disposition_Time__c_Day') in [dateRange([2017,12,05], [2018,12,05])];
q2 = filter q2 by 'Data_Re.Week_Num' in ["48"];
q2 = filter q2 by 'Data_Re.Day_Week_Num' in ["1","2","3","4","5"];
q2 = group q2 by ('Disposition_Time__c_Year', 'Disposition_Time__c_Month', 'Disposition_Time__c_Day','Data_Re.Week_Num','Data_Re.Day_Week_Num','Disposition_Date__c','Data_Re.Previous_Week_Num');
q3 = filter q by date('Disposition_Time__c_Year', 'Disposition_Time__c_Month', 'Disposition_Time__c_Day') in [dateRange([2017,12,05], [2018,12,05])];
q3 = filter q3 by 'Data_Re.Week_Num' == "47";
q3 = filter q3 by 'Data_Re.Day_Week_Num' in ["1","2","3","4","5"];
q3 = filter q3 by 'Disposition_Time__c_Year' != "2017";
q3 = group q3 by ('Disposition_Time__c_Year', 'Disposition_Time__c_Month', 'Disposition_Time__c_Day','Data_Re.Week_Num','Data_Re.Day_Week_Num', 'Data_Re.Previous_Week_Num','Disposition_Date__c');
q3 = foreach q3 generate  'Data_Re.Day_Week_Num' as 'Data_Re.Day_Week_Num', 'Data_Re.Previous_Week_Num' as 'Data_Re.Previous_Week_Num', 'Disposition_Date__c' as 'Disposition_Date__c';
q2 = foreach q2 generate 'Data_Re.Day_Week_Num' as 'Data_Re.Day_Week_Num', 'Data_Re.Previous_Week_Num' as 'Data_Re.Previous_Week_Num', 'Disposition_Date__c' as 'Disposition_Date__c';
qtot= cogroup q2 by ('Data_Re.Day_Week_Num'),q3 by ('Data_Re.Day_Week_Num');
qtot= foreach qtot generate q3.'Data_Re.Day_Week_Num' as 'Data_Re.Day_Week_Num', q2.'Disposition_Date__c' as 'Disposition_Date__c2', q3.'Disposition_Date__c' as 'Disposition_Date__c3';

Has anyone done something similar? Thanks for any help you can provide!