I've successfully produced my background image and have "Position" plotted on it.
(Thanks to the training video (Mapping Background images using the Hong Kong metro) and also Ryan Sleeper's TC16 presentation "How to Map anything in Tableau" (baseball pitch) which were both easy to follow.)
But I'm having a conceptual block when it comes to linking my data to the background image data.
I created a calculated field called "Position" hoping to use it as a linked dimension. However, it's a Measure and I can't change it to a Dimension.
(In case you are interested to know the background to this diagram I've attached pages from an excellent Knowledge Management text "Learning to Fly". The diagram is used to support a community of practice by identifying which members are suppliers of knowledge and which are consumers. )
Helen
Hey Helen,
First of all, for your future reference, the reason you are not able to make your calculated field a Dimension, is because it uses aggregation in the calculation (SUM), and therefore cannot be associated with each row in the data (this is at least one way I think of it).
Secondly, an easier way for you to map your data onto your desired image would be to do the following (I include some cleaner calculations as well);
1)Change the [Answer] dimension data type to Number (Whole) by right clicking on the dimension, then you can drag it down to the measures pane
2)Simplify the Target and Performance calculations to the following
3) Create a new calculation for Gap. Because these are two different rows in the data (performance and target), an LOD calc could work well for finding the Target for a particular email, and practice combination.
4)Instead of needing to blend with a reference table, you can just use these calculation to map your background image into this dataset. Just create the following conversion calculations;
5)Map the background image to these calculations
6) Places these measures on the rows and columns. Right click and make them 'Discrete' and 'Continuous'. Then place your measure, like Count Distinct of Email on the marks card. Resulting in the following;
This was longer than expected, but hope it helps!
-Travis
