A previous post on the 'fullGenLapack' eigenvalue solver led me down a rabbit hole of sorting out all the equation solvers (linear and eigen) and equation numberers available in OpenSees. I have yet to emerge from the rabbit hole, but I wanted to show how to create "spy" matrices from OpenSees models. A spy matrix … Continue reading OpenSees Spy →

In a previous post, I showed how equation numberers can reduce the bandwidth of the tangent stiffness matrix. In addition to reducing the solution time for linear systems of equations, a smaller bandwidth reduces the data required to store the tangent stiffness matrix. To discuss matrix storage in this post, I'll use the frame model … Continue reading Make Room for Storage →

For large structural models, the solution to $latex {\bf K}_T\Delta {\bf U}={\bf R}$ can be the computational bottleneck during an analysis. Although computing speed and algorithms to solve $latex {\bf K}_T\Delta {\bf U}={\bf R}$ are very good, you still want to make sure the solution happens as quickly as possible, particularly when inside the double … Continue reading Reduce Your Bandwidth →