The (discrete) cumulative distribution function of the Poisson distribution
This functionality does not run in MATLAB.
stats::poissonCDF(m) returns a procedure
representing the (discrete) cumulative distribution function
of the Poisson distribution with mean
f := stats::poissonCDF(m) can
be called in the form
f(x) with arithmetical expressions
The return value of
f(x) is either a floating-point
number, an exact numerical value, or a symbolic expression:
x is a numerical real value, then an explicit
value is returned. It is a floating-point number if
a floating-point number and
m can be converted
to a positive real float. Otherwise, an exact expression is returned.
x is a numerical value
returned for any value of
For symbolic values of
the symbolic call
Numerical values for
m are only accepted
if they are nonnegative.
x is a real floating-point number, the
result is a floating number provided m is
a nonnegative numerical value. If both
exact numerical values, the result is an exact number.
Note that for large m,
floating-point results are computed much faster than exact results.
If floating-point approximations are desired, pass a floating-point
The function is sensitive to the environment variable
determines the numerical working precision.
We evaluate the distribution function with
f := stats::poissonCDF(1/2): f(-PI) = f(float(-PI)), f(0) = f(0.0), f(4) = f(4.0)
We use symbolic arguments. If
x is symbolic,
a symbolic call is returned:
f := stats::poissonCDF(m): f(x)
x is a numerical value, symbolic expressions
m are returned:
f(-1), f(0), f(5/2), f(PI)
When numerical values are assigned to m, the function f starts to produce explicit results if the argument is numerical:
m := 3: f(-1), f(0), f(5/2), f(PI)
delete f, m:
The mean: an arithmetical expression representing a nonnegative real number