  We study the Bose-Einstein condensation of an interacting gas with attractive
interaction confined in a harmonic trap using a semiclassical two-fluid
mean-field model. The condensed state is described by converged numerical
solution of the Gross-Pitaevskii equation. By solving the system of coupled
equations of this model iteratively we obtain converged results for the
temperature dependencies of the condensate fraction, chemical potential, and
internal energy for the Bose-Einstein condensate of $^7$Li atoms.
