1. A non-transitory computer storage medium having stored thereon computer program code that, when executed by a processor, performs the steps of: generating a layout of an electronic circuit; generating abstract data at a level of a substrate that are associated to the layout of said electronic circuit; generating a grid of partitioning, with respect to a view regarding said abstract data, into meshes and nodes and applying it to said substrate; and extracting, on the basis of said partition grid, a list of nodes or netlist representing a thermal network that represents the thermal behavior of the substrate or of portions or elements of the substrate, wherein said netlist is configured for use in simulation operations, in particular of a SPICE type, for making an evaluation of said thermal effects in said electronic circuit; and supplying said netlist to one of an operation of simulation of the thermal behavior and an operation of coupled electro-thermal simulation which simulates simultaneously both the electrical behavior and the thermal behavior of the electronic circuit or of a device thereof, taking into account the interactions with the electronic circuit or with parts thereof.