Abstract: A method for structural analysis and correction of a system of differential equations described by a computer language is disclosed. A description of a physical system (in the form of equations, in particular differential equations) as a computer program in a computer system is included. Suitable bipartite graphs for examining the solubility of the equations are generated with the method. Erroneous descriptions can be determined and can possibly be corrected with the bipartite graphs. A computer system containing a computer-readable medium having computer-executable instructions for performing the method, and a corresponding data carrier are disclosed.

Abstract: An image is used to diagnose an electric circuit having a multiplicity of elements. The image includes a network graph and a system of equations. The network graph contains dynamic elements for which voltage values can be preset. In order to handle such defaults correctly, statements are made to indicate the dynamic elements for which no values can be preset, and a subsidiary network graph is established in which the dynamic elements of the network graph are replaced by suitable current sources and by voltage sources. A DC-solvable system of equations is produced using the information from the network graph thus modified. The solution of the system of equations thus obtained corresponds to the defaults for the initial value of the original system.

Abstract: A method for structural analysis and correction of a system of differential equations described by a computer language is disclosed. A description of a physical system (in the form of equations, in particular differential equations) as a computer program in a computer system is included. Suitable bipartite graphs for examining the solubility of the equations are generated with the method. Erroneous descriptions can be determined and can possibly be corrected with the bipartite graphs. A computer system containing a computer-readable medium having computer-executable instructions for performing the method, and a corresponding data carrier are disclosed.