| Pré. | Proc. |
spence
Dilogarithm.SYNOPSIS:
double x, y, spence();
y = spence(x);
DESCRIPTION:
Computes the integral:
x
-
| | log t
spence(x) = - | ----- dt
| | t - 1
-
1
for x >= 0. A rational approximation gives the integral in the interval (0.5, 1.5). Transformation formulas for 1/x and 1-x are employed outside the basic expansion range.
ACCURACY:
Relative error:
arithmetic domain # trials peak rms
IEEE 0,4 30000 3.9e-15 5.4e-16
DEC 0,4 3000 2.5e-16 4.5e-17