# A Step-by-Step Guide to Creating a Craps Game in Power BI

## Introduction

Craps is a popular casino game played with a pair of dice. The objective is to predict the outcome of a dice roll, and place bets accordingly. In this tutorial, we will walk you through creating an interactive Craps game within a Power BI report. We will explain the data structure required, how to set up tables and measures, and implement DAX formulas. This guide is designed for beginners and assumes no prior experience with Power BI or Craps.

1. Prepare the data structure

To create a Craps game in Power BI, we will need three separate tables: Bets, Rolls, and Outcomes. The tables should have the following structure:

a. Bets

• BetID (unique identifier)
• BetType (Pass Line, Don’t Pass Line, etc.)
• Amount (the amount wagered)

b. Rolls

• RollID (unique identifier)
• Roll1 (value of the first die, between 1 and 6)
• Roll2 (value of the second die, between 1 and 6)

c. Outcomes

• OutcomeID (unique identifier)
• RollTotal (sum of Roll1 and Roll2)
• Outcome (Win, Lose, or Continue)
1. Load data into Power BI

Import the tables into Power BI. For this tutorial, you can use sample data or create your own. Click on ‘Home’ > ‘Get Data’ > ‘Excel’ (or any other source) and load the tables into the data model.

1. Create relationships between the tables

Once the tables are loaded, go to the ‘Model’ tab, and create relationships between the tables. Connect ‘Bets'[BetID] to ‘Rolls'[BetID], and ‘Rolls'[RollID] to ‘Outcomes'[RollID]. This will allow us to analyze the data and create DAX measures easily.

1. Set up the report layout

Create a new report page and add the following visuals:

a. Slicer for selecting the BetType. b. Table for displaying the Bets, Rolls, and Outcomes. c. Buttons for rolling the dice and placing bets.

1. Implement DAX measures

We will need several DAX measures to control the game logic and calculate the outcomes. Some examples include:

a. RollDice = RANDBETWEEN(1,6)

• This formula generates a random number between 1 and 6, simulating a dice roll.

b. TotalRoll = [Roll1] + [Roll2]

• This measure calculates the sum of the two dice rolls.

c. GameStatus = VAR Result = SWITCH ( TRUE (), [TotalRoll] = 7 || [TotalRoll] = 11, “Win”, [TotalRoll] = 2 || [TotalRoll] = 3 || [TotalRoll] = 12, “Lose”, “Continue” ) RETURN Result

• This measure calculates the outcome based on the sum of the dice rolls.
1. Assign DAX measures to visuals

Once the DAX measures are created, assign them to the appropriate visuals. For example, add the ‘RollDice’ measure to the button for rolling the dice, and the ‘GameStatus’ measure to the Outcomes table.

1. Set up interactions between visuals

To make the game interactive, set up actions and interactions between the visuals. For example, create a ‘Roll Dice’ button that triggers a new dice roll and updates the ‘Rolls’ table.

1. Test and refine the game

Now that the game is set up, test it thoroughly to ensure it works as expected. Make any necessary

adjustments to the DAX measures or visuals, and refine the game for optimal performance and user experience.

1. Customize the report’s appearance

To make your Craps game more visually appealing, customize the report’s appearance using themes, colors, and fonts that suit your preferences. You can also add images or other design elements to enhance the overall look.

1. Publish and share the report

Once you’re satisfied with your interactive Craps game, publish it to the Power BI service. Share the report with colleagues or friends, so they can enjoy playing the game as well.

Chris’s Note – I pointed out to ChatGPT that it hadn’t incorporated the point system into the Craps game, so the following section is needed to properly have a true Craps game.

Let’s incorporate the point system into the Craps game simulation in Power BI. We will need to modify the data structure and DAX measures to account for the point system rules.

1. Update the data structure

Modify the ‘Outcomes’ table to include a new column:

• Point (the point number that the player must roll again before rolling a 7 to win)
1. Modify the GameStatus DAX measure

We need to update the GameStatus measure to account for the point system rules. The new measure should look like this:

``````GameStatus =
VAR Point = IF ( [TotalRoll] >= 4 && [TotalRoll] <= 10 && [TotalRoll] <> 7, [TotalRoll], BLANK() )
VAR Result =
SWITCH (
TRUE (),
ISBLANK ( Point ) && ( [TotalRoll] = 7 || [TotalRoll] = 11 ), "Win",
ISBLANK ( Point ) && ( [TotalRoll] = 2 || [TotalRoll] = 3 || [TotalRoll] = 12 ), "Lose",
NOT ( ISBLANK ( Point ) ), "Point"
)
RETURN
Result
``````

This measure first calculates the point number (if applicable) and then determines the outcome based on the total roll and point number.

1. Create a new DAX measure for tracking the point

We need a separate measure to keep track of the point number across multiple rolls.

``````CurrentPoint =
VAR CurrentOutcome = SELECTEDVALUE ( Outcomes[Outcome] )
VAR CurrentPoint = SELECTEDVALUE ( Outcomes[Point] )
RETURN
IF ( CurrentOutcome = "Point", CurrentPoint, BLANK() )
``````
1. Update the GameStatus DAX measure again

We need to modify the GameStatus measure once more to account for the point system rules when the player has an active point number.

``````GameStatus =
VAR CurrentPoint = [CurrentPoint]
VAR Result =
SWITCH (
TRUE (),
NOT ( ISBLANK ( CurrentPoint ) ) && [TotalRoll] = CurrentPoint, "Win",
NOT ( ISBLANK ( CurrentPoint ) ) && [TotalRoll] = 7, "Lose",
[TotalRoll] = 7 || [TotalRoll] = 11, "Win",
[TotalRoll] = 2 || [TotalRoll] = 3 || [TotalRoll] = 12, "Lose",
"Continue"
)
RETURN
Result
``````

Now, the GameStatus measure will calculate the outcome based on the total roll, point number, and whether the player has an active point number.

1. Update the report layout and visuals

You may need to update your report visuals to display the new information, such as the point number and the updated GameStatus. You can create a card visual to display the CurrentPoint measure and add the updated GameStatus measure to the Outcomes table.

With these updates, the Craps game simulation in Power BI should now correctly implement the point system rules. Players will need to roll their point number again before rolling a 7 to win, as per the standard Craps rules.

## Conclusion

In this tutorial, we walked you through creating an interactive Craps game in a Power BI report. We covered the data structure, creating tables and relationships, setting up the report layout, implementing DAX measures, and refining the game. By following these steps, even beginners can create a fun and engaging Craps game in Power BI. Enjoy playing and sharing your game with others!

This blogpost was created with help from ChatGPT Pro.