I think I understand what you are asking for. There is a way that we can do this and it uses the level of detail shelf.
First you want to create a calculation that returns the difference between the start and the end of a project. Similar to this:
DATEDIFF('day',[Order Date],[Ship Date] )
You will use your current chart type of a horizontal Gantt bar. You will place this duration calculation on size. Remember to turn your date dimension to continuous and chose all values.
The level of detail shelf is where you will put your intermediary dates. Be sure that these are also continous and set to all values.
The last step is to format the marks by turning borders on. This will now show you the lines at each phase in the process.
I have attached a workbook using a sample data set that helps illustrate this point.
Hopefully this is of some help.
~Jeff Mills, Tableau Software.
Project Timelines.twbx 968.7 KB
Hello, Alex and Jeff.
After looking at Jeff's workbook, I started thinking (bad policy). The result is the attached, revised version of your workbook, Jeff. The main items of interest are:
Your viz begged the question for me if there were overlapping marks, and what does this mean for Alex's objectives. In the attached, see the the sheet, "Are There Overlaps?". There are clearly overlapping marks.
So then the question is, "Why?" One reason might be the Ship mode is obscured. See the sheet, "Step 1: Add Ship Mode to Color Shelf". It adds Ship Mode to the Color Shelf, and uses the transparency slider to explore potential overlaps and tease out the Ship Mode.
This leads to the next question, whether Order ID can shed more light on the overlaps matter. Sure enough, take a look at sheet, "Step 2: Add Order ID to Row Shelf".
And because there are now still overlaps, adding Ship Mode also to the Row Shelf ("Step 3: Add Ship Mode to Row Shelf") reveals that indeed some orders have multiple Ship Modes, effecting the Days to Ship.
Getting back to Alex's thinking about the viz, can the concept of met/blew a deadline be incorporated here. See sheet, "Step 4: Expand Ship Mode Indicator to Include Deadline Evaluation", for the obvious answer, based on Alex's criterion. Shades of the same color within Ship Mode to indicate whether a deadline was met.
Step 5 , Step 6, and Step 7, apply this approach to the original Sheet1 viz in Jeff's workbook.
Any thoughts? Does this approach help, Alex?
Peace and All Good!
Michael W Cristiani
MARKET INTELLIGENCE GROUP
Project Timelines_alt.twbx 1.1 MB
Michael et al,
Thanks for the nice workbook with timelines. It goes part of the way towards what I'm asking for.
But I think Tableau could still use some new features (I suggest with datetime annotations, but perhaps in some other way) to be better able to show detailed timeline data.
Especially when showing both time "intervals" (e.g. ghant bars showing tasks with durations) and time "instants" (points in time, e.g. deadlines), and also phase transitions (task goes through multiple phases before completing)
I tried to illustrate a bit in the attached workbook.
Note how poorly text annotations work as a way to show deadlines on the first worksheet.
P.S. One trick I noticed after first posting this is that you can approximate a point marker by making a mark annotation with no text and no line, just an arrowhead (and then positioning the arrowhead).
One reason that doesn't work well is that its difficult to position the arrowhead exactly, you can't change the arrowhead icon beyond a few simple choices or color, and most importantly the position of the arrowhead is not drawn from the data, but is positioned by hand. That obviously doesn't scale up.
Timeline_Example2.twbx 14.5 KB