Tag: Distinct Count

  • Measures – Intelligent Card Visual – Using DAX

    Measures – Intelligent Card Visual – Using DAX

    As I have been exploring PowerBI and building dashboards I have noticed that often the visuals can obscure your data.  As you click on different visuals there is a need to highlight different pieces of data.  Take for example the following dashboard:

    Sample Visual Example
    Sample Visual Example

    Notice the different car types in the bar chart.  As you click on each vehicle type, Diesel, Hatchback, etc.. you expect the data to change accordingly.  In some cases it is helpful to present a card visual to show the user what you selected and any relevant data points you want to highlight.  For example if I select the Diesel vehicle type I may want to know the average sales amount, total sales in dollars, or number of units sold.  This is where we can build specific measures that will intelligently highlight selected data within your PowerBI visual.

    Here is a sample of what we will be building today:

    lets begin with starting with some data.  In honor of your news feed being bombarded with Pokemon Go articles lets enter some data on Pokemon characters.

    We will enter our data manually.  For a full tutorial on manually entering in data visit here.

    Click the Enter Data button on the Home ribbon and enter the following information into the displayed table.

    Pokemon XP
    Pikachu 1200
    Weedle 650
    Pidgey 800
    Golbat 300

    Rename the table to Characters.  Once you are finished entering in the data it should look like the following:

    Create Table of Characters
    Create Table of Characters

    Click Load to continue.

    Start to examine your data by building a table visual.

    Table Visual
    Table Visual

    Next add a Bar chart.

    Bar Chart
    Bar Chart

    Note: I added the XP column twice.  Once to the Value attribute and to the Color Saturation.  This enhances the look of your visual by coloring the bars with a gradient.  The largest bar will have the darkest color, and the smallest bar will have the lightest color.

    Next, we will begin building some measures.  The first measure will be a total of all the experience points (XP) for each character. Click the New Measure button on the Home ribbon and enter the following DAX expression:

    Total XP = Sum(Characters[XP])

    Now, add a Card visual and add the new measure we created Total XP.

    Total XP Card Visual
    Total XP Card Visual

    This measure totals all the experience points for all the selected characters within the visual.  Since all characters are now selected the total XP for all characters is 2,950.

    The next, and final measure, will be the intelligent card.  For this measure we want to display the characters name when we select them in the bar chart.  Click the New Measure button on the Home ribbon and enter the following DAX expression:

    Character(s) = IF( DISTINCTCOUNT(Characters[Pokemon]) = 1 , FIRSTNONBLANK('Characters'[Pokemon],'Characters'[Pokemon]) , DISTINCTCOUNT('Characters'[Pokemon]) & " Selected")

    Update: As of Mid 2017 Microsoft introduced a new DAX expression called SELECTEDVALUE which greatly simplifies this equation.  Below is an example of how you would change the DAX equation to use SELECTEDVALUE.

    Selected = SELECTEDVALUE(  Characters[Pokemon],  DISTINCTCOUNT(  Characters[Pokemon]  )  &  " Selected" )

    Explanation of this measure:

    This measure first checks to see how many distinct items are in the column Pokemon of our dataset.  If there is only one selected character then we will display the FIRSTNONBLANK character, which will be the name of our selected character.  If there are more than one characters selected. The measure will count the number of characters selected and return a text string with the count and the word SelectedThus, showing us how many items have been selected.

    Add the measure titled Character(s) to a card visual.

    Add Character Card Visual
    Add Character Card Visual

    We can now see that there are 4 characters selected.  Clicking on Pikachu in the bar chart resolves with the character’s name being displayed and the XP of Pikachu being displayed in the Total XP card visual.

    Selecting Pikachu
    Selecting Pikachu

    You can select multiple items by holding down Ctrl and clicking multiple items in the bar chart.

    Selecting Pikachu and Pidgey

    Well, that is it.  I hope you enjoyed this Pokemon themed tutorial.  Thanks for visiting.

    Want to learn more about PowerBI and Using DAX.  Check out this great book from Rob Collie talking the power of DAX.  The book covers topics applicable for both PowerBI and Power Pivot inside excel.  I’ve personally read it and Rob has a great way of interjecting some fun humor while teaching you the essentials of DAX.