Application of ALTPACK to the Solution of Nonlinear PDEs. In this article the author applies the alternating-triangular method (ATM) to the solution of a number of 2D initial-boundary value problems that can be modelled by non-linear parabolic equations with a source term. Different types of non-linearities are considered and the procedure of finding approximate solutions is explained. The main features of the ALTPACK package are outlined and the results of computational experiments are presented. ...