gamma(x) lgamma(x)
x.
This function will be used as the default method for classes that do not inherit a specific method for the function or for the Math group of functions. The result will retain the class and the attributes. If this behavior is not appropriate, the designer of the class should provide a method for the function or for the Math group
NAs are returned when evaluation would cause numerical problems,
except that when an overflow occurs, an infinity is returned.
These are members of the
Math group of generic functions.
gamma(x)
increases very rapidly with
x. Use
lgamma
to avoid overflow.
For positive integral values,
gamma(x) is (x--1)!. For
negative integral values,
gamma(x) is undefined.
See
family for the family generating function
Gamma used with the
glm
and
gam functions. See
GAMMA for the functions related to the
gamma distribution:
dgamma (density),
pgamma (probability),
qgamma
(quantile),
rgamma (sample).
gamma(6) # same as 5 factorial lgamma(20) # natural log of gamma(20) digamma(6) # derivative trigamma(6)# second derivative