Aggregate bins in Tableau

Question

I want to aggregate bins in tableau.

See the following figure:

I want to aggregate (merge) the NumberM from 6 untill 16 in one category. 5+/(6 and higher) for example and sum the values of 6-16 in that category. I think this can be done with a few simple clicks but I am not able to manage.

Thanks in advance,

Tim

Solution 1

Answering my own question: With Tableau 9 this can be easily done with the increased flexibility of the level of detail expressions (LOD). I can really recommend this blog on that subject and many more Tableau functions.

Solution 2

There are several ways to classify data rows into different groups or classes: each with different strengths.

• Create a calculated field As emh mentioned, one approach is to create a calculated field to assign a value to a new field indicating which group each data row belongs to. For the effect you want, the calculated field should be discrete (blue). If your calculation doesn't return a value for in one case, e.g. an if statement without an else clause, then the field will be null in that case which is a group in itself. This is a very general approach, and can handle much more complex cases. The only downsides are the need to maintain the calculated field definition and that the cutoff values are hard coded and by itself can't be changed dynamically via a control on the view. BUT those issues can by easily resolved by using a parameter instead of a numeric literal in your calculated field. In fact, that's probably the number one use case for parameters. If you think in SQL, a discrete field on a shelf is like a group by clause.

• Use a filter If you only want a subset of the data in your view, e.g. data rows with NumberM in [6, 16] then you can drag the NumberM field onto the filters shelf and select the range you want. Note for continuous (green) numeric fields, filter ranges include their endpoints. Filters are very quick and easy to drop on a view. They can be made dynamically adjustable by right clicking on them and creating a quick filter. Its obvious from the view that a filter is in use, and the caption will include the filter settings in its description. But a filter doesn't let you define multiple bins. If you think in SQL, a filter is like a where clause (or in some cases using the condition tab, like a having clause)

• Define histogram bins If you want to create regular sized bins to cover a numeric range, such as values in [1,5], [6,10], [11-15] ..., Tableau can create the bin field for you automatically. Just right click on a numeric field, and select Create Bins.

• Define a group Very useful for aggregating discrete values, such as string fields, into categories. Good for rolling up detail or handling multiple spellings or variants in your data. Just right click on a field and select Create Group. Or select some discrete values on an axis or legend and press the paperclip option. If you then edit a group, you'll see what's going on. If you think in SQL, a group is like a SQL case statement.

• Define a set Another way to roll up values. The definition of a set can be dynamically computed or a hard coded list of members. Both kinds are useful. You can combine sets with union, intersection, set difference operators, and can test set membership in calculated fields. Sets are useful for binary decisions, rows are divided into those that are members of the set and those that are not.

Filters, sets, groups, calculated fields and parameters can often be combined to accomplish different effects.

Most if not all of these features can be implemented using calculated fields, especially if the business rules get complicated. But if a filter, bin, group or set fits your problem well, then it's often best to start with that, rather than define a calculated field for each and every situation. That said, learning about the 4 kinds of calculated fields really makes a difference in being able to use Tableau well.

Solution 3

You can do this with calculated fields.

Go to: Select Analysis > Create Calculated Field.

Then use this formula:

IF NumberM > 5 THEN "OVER 5"

You can then use that calculated field as a filter on the worksheet in your screenshot.