Visual Poisson Distribution Calculator

Poisson distribution is so important that I had to learn it in a recent project. Learnt to use it to be exact.

Thus came an idea to visualize it in Tableau, because I couldn't find a good visual reference on the web about it.

Here you go. It shows two charts:
1.Probability distribution per K (the number of occurrences).
2.Cumulative probability for all events where the number of occurrences <=K.
3.Both λ and the range of K are in parameters.

Click image to view the interactive version.

You might notice that we need to calculate the factorials of K in Poisson distribution. The initial calculation formula failed because the numbers were too big for integer operations. A workaround is found using floating point calculations.

[Update]Added an alternative view that highlights the complementary property of <=K and >K probabilities:

Click image to view the interactive version.