Pré. | Proc. |
beta
Beta function.SYNOPSIS:
double a, b, y, beta();
y = beta(a, b);
DESCRIPTION:
- -
| (a) | (b)
beta(a, b) = -----------
-
| (a+b)
For large arguments the logarithm of the function is evaluated using lgam(), then exponentiated.
ACCURACY:
Relative error:
arithmetic domain # trials peak rms
DEC 0,30 1700 7.7e-15 1.5e-15
IEEE 0,30 30000 8.1e-14 1.1e-14
ERROR MESSAGES:
message condition value returned
overflow log(beta) > MAXLOG 0.0
a or b <0 integer 0.0