Greetings MATPower community, I had a question about the way sparsity-based techniques are used in the Newton-Raphson solver of the power flow algorithm in MATPower.
I ran the code step-by-step and from my understanding, the way the sparsity of the Jacobian matrix is exploited is that it is created as a MATLAB "sparse" matrix wherein only the non-zeros are stored with the respective matrix positions and then the MATLAB operator "\" is invoked while calculating dx = -(J \ F); where J is the Jacobian and F is the vector of mismatches. MATLAB "\" by default exploits the sparsity of the matrix by using a LU solver. The kind of solver "\" uses actually depends on the matrix structure if it is diagonal/tridiagonal/banded and so on (Flowchart obtained from Mathworks website attached in the email). I assume based on the typical structure of the Jacobian that an LU solver is most likely to be chosen. Is my understanding correct or am I missing something out? Thank you for your time and effort. -- Best Regards, Shruti Dwarkanath Rao Graduate Research Assistant School of Electrical, Computer and Energy Engineering Arizona State University Tempe, AZ, 85281 650 996 0116
