Go to the first, previous, next, last section, table of contents.
Lambert's W functions, @math{W(x)}, are defined to be solutions
of the equation @math{W(x) \exp(W(x)) = x}. This function has
multiple branches for @math{x < 0}; however, it has only
two real-valued branches. We define @math{W_0(x)} to be the
principal branch, where @math{W > -1} for @math{x < 0}, and
@math{W_{-1}(x)} to be the other real branch, where
@math{W < -1} for @math{x < 0}. The Lambert functions are
declared in the header file `gsl_sf_lambert.h'.
- Function: double gsl_sf_lambert_W0 (double x)
-
- Function: int gsl_sf_lambert_W0_e (double x, gsl_sf_result * result)
-
These compute the principal branch of the Lambert W function, @math{W_0(x)}.
- Function: double gsl_sf_lambert_Wm1 (double x)
-
- Function: int gsl_sf_lambert_Wm1_e (double x, gsl_sf_result * result)
-
These compute the secondary real-valued branch of the Lambert W function,
@math{W_{-1}(x)}.
Go to the first, previous, next, last section, table of contents.