There are cases where we have bar charts whose centerline is not zero, for example when we’ve indexed a measure to have a base of 100. Here’s an example where the SUM(Sales) for each product Category is indexed to the average sales per Category:
What happens when we want the bars to start at 100 and then go up or down from there, like this?
Stacked bar charts can put the mark labels in the middle of the bars, so we can use Measure Values with the measure of interest and a measure that returns Null to create the stacked bars. The Null measure won’t show anything, while the measure’s label will be in the proper location.
The measure that returns Null needs a formula like IF 1=0 THEN 0 END, if just Null is used then Tableau forces that to be a True/False dimension, and that won’t work.
Measure Names must be in the level of detail of the view (LoD Shelf, Colors Shelf, etc.) on the Level of Detail Shelf for this to work, that’s part of what forces Tableau to properly stack the bars.
length of bars is whatever is on columns or rows shelf (stacked or unstacked) Size shelf determines thickness of bars size slider adjusts thickness mark label is pinned to the end of the bar
Gantt Bar chart
starting position of bars is whatever is on columns or rows shelf Size shelf determines length of bars Size slider changes thickness mark labels can be set to beginning, middle, or end of bar Note in Tableau v6.1 the mark label alignment has only one value for all measures with Gantt Bar marks on the same chart. In Tableau v7, the mark label alignment can vary for each measure.
This section covers a whole bunch of chart types that are not part of Show Me, but can be built in Tableau, along with some notes on how to get existing charts to work more like I want them to. There’s also a whole section on the Path Shelf.
On blood transfusion data, getting a table calc to have connected points for a line chart:
Notes from Mar 2012 WebEx w/Joe Mako
I don’t want to misrepresent Joe’s awesome knowledge here, if there are any mistakes in these notes from our conversation they are almost certainly mine.
In Tableau v7.0, the Tableau DATETRUNC() from the pill menu doesn’t work. 1. Turn Quarter into Continuous field using DATE(DATETRUNC(‘quarter’,[date field])) 2. Set to Exact Date – Continuous 3. Put Month([date field]) on Path Shelf. Note – when on LoD it causes partitioning, when on Path shelf it helps connect marks 3. Then for each measure (axis) select the pill->Format->Hide…Connect Lines
Make sure that both fields have the same datatype. One way to check to see what data type Tableau is recognizing a field as is to open the calculated field box, select the desired field and in the yellow box at the bottom right will tell what type of field it is. Note that datatype and number format are independent! See this thread on what can happen when you try mark labels on a dual axis chart without synchronized axes: http://community.tableausoftware.com/thread/114593
This is a post about getting the output you want, despite what Tableau thinks.
This is a post about making Tableau do what Excel can do (whether it’s a good idea or not).
This is a post about gaining better understanding of dimensions, measures, continuous, and discrete.
This is a post about putting bars and lines on the same chart. Continue reading →