通过子列值计算列值

Question

I know this will require an advanced custom expression - I have 2 relevant columns, commodity and sub-commodity. A single event can have multiple commodities and sub-commodities. However, some commodities will naturally have more data about them. I don't want this to skew representation of the data.

I want to avoid that by counting values by their unique sub-commodity. In the below example, I want the bar chart to represent two instances of food for Event 1 (1 for meat, 1 for beverages) and one instance of garden for Event 2. How do I accomplish this?

EventID | Commodity | Sub-Commodity
  1         Food         Meat
  1         Food         Meat
  1         Food         Beverages
  2         Garden       Lawn Mower
  2         Garden       Lawn Mower   

Answer 1

Thanks for the sample data. It helps in providing an answer.

You should be able to do this by using the UniqueCount() function. In this case the Y axis would be the expression UniqueCount([Sub-Commodity]). You can use custom expressions to input this or use the built-in drop down and select UniqueCount from the aggregation drop-down.

Take a look at the below image showing my implementation with a custom expression. Coloring is optional but I did so to show how it included your multiple sub-commodities and how they were counted (1 for Food=>Meat).

See below for an example with the drop-down:

Let me know if you have any questions or need further clarification. Thanks!