In a recent post I introduced using R custom Visuals in Power BI, and this post details how to use the correlation visual in a Power BI Report. The first step in the process is to download R, if it is not on the computer already. if SQL Server 2016 with R integration is installed, there is no need to download R, as it was installed already. If the computer does not have R installed, click here. Once R is installed, go to the Power BI Custom Visualization page and select the R tab to pick one of the six R visualizations. I picked the correlation plot. To use the R visualization, if the machine does not already contain the packages used in the visualization, as screen will prompt you to install some packages also. This may take a little while to do and when it is complete, a window will appear showing the packages were successfully installed. Now the custom Visual can be used in Power BI.
Using the Correlation Visualization in Power BI
Power BI will show the new visual which you can place on the report. It is important to understand a little about R to better understand the error messages received. For example if you are using the forecasting tool and have selected the year value instead of the date, you may receive an error about an invalid time series. The underlying code is expecting to receive a date value, and a year is not a date, meaning you have to reference a date field in order to make it work.
Differences between R Visualizations and other Power BI Visualizations
Interacting with R visuals works differently than with other report visualizations as you cannot click on elements within the visualization and filter other items on the page. Other visuals on the page will filter the data contained within the R visual. For example, let’s say my report contains a total field, a slicer which contains years and a correlation plot which contains products. If the slicker is changed to select a year, total field and the data within the R visual will change to reflect that. If on the other hand, I choose to click on the R visual to select one of the product categories, the total field will not change and the R visual will not change. The R visual’s appearance will not change in any way.
One interesting thing to note is if you have created an R visual in Power BI and are working without an internet connection, the report will throw an error when trying to open the report. This occurred when it was a report I created or a sample report, so it appears with these reports an internet connection is required.
Data aficionado et SQL Raconteur