Monday 28 March 2016

Tableau Hex Map for Europe

Solved the problem I was having with different parts of the dashboard having different colour schemes - after filtering.  I had been assigning colours per worksheet - you need to reset these if you've done it and go back to the original field in the data and set the colour there. (Hint was from the kind answer to this question.)

Obvious, really.

I also managed to get rid of the persistent axis. Right clicking in the row or column shelf and choosing format, click on the 'line' option (a brush) in the format and here was a case where it had not already been set to 'none' (in spite of trying!).


Sunday 27 March 2016

Tile-based maps and Service Unit Forecasts

I have been experimenting with tile-based maps in Tableau.

The use-case is showing growth of total en route service units (actual and forecast), and using the map as a way to select a subset of a large table. The data are from the EUROCONTROL/STATFOR forecast (Feb 16, Annex 5).

The place to start for hints on how to do this in Tableau is Sir Vizalot, though some of the links in this seem to be broken.

My specific steps were:
1) I'm interested in a specific set of European States. I used 'keynote' (powerpoint) to create hex tiles and move them around until I had an initial layout of European countries I thought was reasonable.
2) I converted this into a table of coordinates, using the ISO 2-letter country codes (and using IA and IC for Azores and Canaries, respectively).
3) I pulled these data into Tableau, including a translation table from ISO to EUROCONTROL's ICAO-based State codes. Tableau does a nice job of choosing the right joins.
4) Setting up the hex map follows smoothly using Sir Vizalot's advice, though it took me a while to realise I shouldn't start worrying about size & shape of the 'map' until it was embedded in a dashboard. And the alignment of the labels defaults to off the hex - fixed using the label:alignment option.

A couple of things I'm not yet happy with: the colour scale for the growth legend doesn't seem fully coordinated between the map and bubble plot; and I'm left with an axis which should have been turned off, but is still there. Hints welcome!

Here's what it looks like:



and here's a hex you can load into your Tableau.