cc [ flags ] -I/usr/local/include file(s) -L/usr/local/lib -lmcw [ ... ] #include <mathcw.h> extern float betam1f (float); extern double betam1 (double); extern long double betam1l (long double); extern __float80 betam1w (__float80); extern __float128 betam1q (__float128); extern long_long_double betam1ll (long_long_double); extern decimal_float betam1df (decimal_float); extern decimal_double betam1d (decimal_double); extern decimal_long_double betam1dl (decimal_long_double); extern decimal_long_long_double betam1dll (decimal_long_long_double);
NB: Functions with prototypes containing underscores in type names may be available only with certain extended compilers.
These values are defined by the relations
beta(x) = sum(k = 1:Infinity) (-1)**k (2k - 1)**(-x), betam1(x) = beta(x) - 1, betam1(x) = sum(k = 2:Infinity) (-1)**k (2k - 1)**(-x).
Whole-number arguments are special cases that are computed internally, and quickly, by a call to betnm1(3CW).
For large positive x, the value of beta(x) approaches 1 from below, so this function, betam1(x) should then be used to compute the difference beta(x) - 1 accurately.
If the argument is -Infinity, set errno to ERANGE and return +Infinity.