Aggregate Properties for Groups

This tool aggregates property values to the group object itself from the objects the group contains. The formulas can use constants, group properties, and, of course, building element objects’ properties. The very basic operation is summarizing property values in different ways, but there are other aggregation types available, too.

 

In Simplebim systems, zones, classifications, and type objects are also groups.

 

Settings

There are four different tools for calculating and aggregating properties. They all share common settings, which you can find from the Calculate Properties for Objects tool's documentation.

Here are the settings specific for the Aggregate Properties for Groups tool.

Aggregation type

This option applies when you're using either the for Groups, for Containers, or for Connected Objects tool.

For example, if you want to calculate the sum of the object volumes from the objects assigned to the group, you would choose SUM here.

The options here are Sum, Average, Min, Max, Median, Variance, Count, and Concatenate String.

The basic aggregation types do what their name says. Note that you can calculate Sum, Average, Median, and Variance based on a formula, which produces a numeric result.

Min and Max can be found for any numeric result, but also for dates and times. You could, for example, find the largest volume from all the objects included in the group. Or you could find the latest or earliest date.

For Object Count, your formula must be logical. For example, [Height]>3000. This would calculate the number of objects within the group, whose height is greater than 3000 (in model length units).

For the Concatenate String, the formula can be anything; however, the end result is always converted to text. The values included in the concatenated result will be the unique set of values from all the values calculated based on the formula, instead of including all the values.

Count Empty Values

This setting applies when you are aggregating values. It might be that not all the objects within your groups have a proper value for the properties you use in your aggregation. Say there are objects whose volume is, for some reason, zero or empty, and you want to calculate the average of the volumes. Do you want to include the zero values in your average? Or when finding the minimum value, do you want the non-zero minimum or zero? Set this parameter accordingly.

Concatenate String Separator

This setting applies when you are using the Concatenate String aggregation type. In order to make sense of the result, the value needs to be separated with a separator. This can be anything. A space, hyphen, colon, or semicolon is probably the most common one. For example, if you were to combine the material names and use a hyphen as your separator, the end result would look something like this:

Concrete-Steel-Timber

Example Formulas

For all these examples, you need to use either the Aggregate Properties for Groups or for Containers tool.

The very basic function is to summarize the values produced by the formula. So, it can be sum of just one object property. Set the aggregation type to SUM and input the formula:

[Volume]

Or it could be sum of some calculation like for example weight:

7250*[Volume]

You can find the minimum or maximum value from any measure value property, or calculation result. Just like above, this would find for example the minimum area. Set the aggregation type to MIN and input the formula:

[Area]

… Or you can use any formula, which produces numeric values:

[Group|Workload]*[Volume]

To Concatenate a string from the object properties to the group use something like this. Remember to set the Concatenate String Separator:

[Material]

You can even combine the object identifiers with the Groups own if that makes sense:

[Group|Name] & “-” & [Building Element Construction Type]

And what is cool, the properties you include to the concatenated string don’t even have to be text properties themselves:

[Building Element Construction Type] & “-” & [Height] & “*” & [Width]