--  POISSON.DIST returns the Poisson distribution 
--  Use case: predicting the number of events over
--  a specific time, such as the number of customers
--  entering a store in 1 hour
--      POISSON.DIST ( Value, Mean, Cumulative )
DEFINE
    VAR Mean            = 10 -- Expected number of customers in 1 hour
    VAR Vals            = GENERATESERIES ( 0, 20, 1 )
    VAR CumulativeTrue  = TRUE   -- Cumulative distribution function
    VAR CumulativeFalse = FALSE  -- Probability density function
EVALUATE
ADDCOLUMNS ( 
    Vals, 
    "Poisson Distr.",             -- Probability density function
        FORMAT ( 
            POISSON.DIST ( [Value], Mean, CumulativeFalse ),
            "#,0.00000"
        ),
    "Poisson Distr. Cumulative",  -- Cumulative distribution function
        FORMAT ( 
            POISSON.DIST ( [Value], Mean, CumulativeTrue ),
            "#,0.00000"
        )
)