
1. Re: Dual Axis: correctly pairing Longitudes and Latitudes?
Tracy Rodgers Apr 4, 2013 4:45 PM (in response to Chris Foster)1 of 1 people found this helpfulHi Chris,
Are you able to post a sample workbook (twbx file)?
Tracy

2. Re: Dual Axis: correctly pairing Longitudes and Latitudes?
Chris Foster Apr 4, 2013 7:33 PM (in response to Tracy Rodgers)Hi Tracy 
Thanks for your response! I was able to create a stripped down workbook that demonstrates the problem in its simplest form.
If it worked as intended, when you pressed the play button you'd see two dots moving simultaneously:
* one blue dot travel lefttoright while arcing upthendown
* one red dot travel righttoleft while arcing downthenup
Instead, right now, you see four dots  two red and two blue.
 ChrisF

3. Re: Dual Axis: correctly pairing Longitudes and Latitudes?
Richard Leeke Apr 5, 2013 1:05 AM (in response to Chris Foster)The secret is to transform your data so that you have two rows for each of your current rows  one with the alpha coordinates and one with the beta coordinates. You can either physically restructure your data source or you can do it with a custom SQL statement, as I've done in the attached workbook. Here's the custom SQL:
SELECT
'alpha' AS [type],
[duallonglattestdata#csv].[alpha_x] AS [x],
[duallonglattestdata#csv].[alpha_y] AS [y],
[duallonglattestdata#csv].[time_index] AS [time_index]
FROM [duallonglattestdata#csv]
UNION ALL
SELECT
'beta' AS [type],
[duallonglattestdata#csv].[beta_x] AS [x],
[duallonglattestdata#csv].[beta_y] AS [y],
[duallonglattestdata#csv].[time_index] AS [time_index]
FROM [duallonglattestdata#csv]

4. Re: Dual Axis: correctly pairing Longitudes and Latitudes?
Chris Foster Apr 5, 2013 12:57 PM (in response to Richard Leeke)I wondered if the solution would be to sift the alpha and beta data into separate rows. I was able to use SQL to sift the coordinates as you suggested. Thanks!
As a Tableau novice, I'm curious. Would you consider the separated data to be the "proper" method of recording this sort of information, or is this more about bending the data to Tableau's strengths?
Thanks very much for the help (and to Tracy for the suggestion to provide sample data)!
 ChrisF