Filter the first column of a matrix based on another column

[gsherbon]

I've downloaded all of the transactions from a Quickbooks file.  The client uses the memo field in almost every entry.

I want to create a Matrix table that has the memo field in the first column, but I only want to pull the memo's from a specific account. 

Is it best to do this by creating a measure for the memo field or by creating a secondary table that filters out the data from the other accounts?

Also, I want to be able to pull the memo's for specific time periods (ie Quarterly).

[amitchandak]

@gsherbon ,Can you share sample data and sample output in table format?