LNGAMMA Function
Evaluates the logarithm of the absolute value of the gamma function log |Γ(x)|.
Usage
result = LNGAMMA(x)
Input Parameters
x—Point at which the logarithm of the absolute value of the gamma function is to be evaluated.
Returned Value
result—The value of the logarithm of gamma function log |Γ(x)|.
Input Keywords
Double—If present and nonzero, double precision is used.
Discussion
The logarithm of the absolute value of the gamma function log |Γ(x)| is computed.
Example
In this example, log |Γ(3.5)| is computed and printed.
x = 3.5
ans = LNGAMMA(x)
PRINT, 'log gamma(', x, ') =', ans; PV-WAVE prints: log gamma( 3.50000) = 1.20097
Warning Errors
STAT_NEAR_NEG_INT_WARN—The result is accurate to less than one-half precision because x is too close to a negative integer.
Fatal Errors
STAT_NEGATIVE_INTEGER—The parameter for the function cannot be a negative integer.
STAT_NEAR_NEG_INT_FATAL—The parameter for the function is too close to a negative integer.
STAT_LARGE_ABS_ARG_OVERFLOW—|x| must not be so large that the result overflows.
