The parallel computing capabilities of OpenSeesSP and OpenSeesMP are easily confused. OpenSeesSP runs your script on a single processor with the other processors awaiting instructions on what to do. OpenSeesSP is ideal for assigning subdomains of a large model to each processor. The main processor, processor 0, directs traffic and solves the governing equations of … Continue reading Monte Carlo Simulation with OpenSeesMP
Category: Programming
Is OpenSees Pythonic?
OpenSeesPy is sometimes criticized for not being "Pythonic". But what does "Pythonic" even mean? And does achieving "Pythonic" status matter? From what I gathered in this blog post, Pythonic code uses the idioms, i.e., the specific syntax and constructs, of Python. That definition is circular--an example from the post better demonstrates the meaning. If you … Continue reading Is OpenSees Pythonic?
OpenSees Command Line Arguments
While graphical user interfaces are good for general purpose use, the command line remains the most versatile way to run OpenSees and other computer programs. Passing command line arguments to an OpenSees Tcl or Python script is useful when creating standalone applications for building and analyzing specialized models. Both Tcl and Python have constructs similar … Continue reading OpenSees Command Line Arguments
How to Use with with OpenSeesPy
The with command offers a clean approach to manage Python resources, particularly file streams. Without going into detail, the with command is a shortcut for exception handling. The nice thing about reading and writing files using the with command is you don't have to worry about closing the file stream. Immediately after the with block … Continue reading How to Use with with OpenSeesPy
A Better Way to Find Memory Leaks in OpenSees
In a previous post, I explained how to find a memory leak in OpenSees. The basic idea was to put the analysis inside a loop, run the loop a million times, and monitor your operating system for increasing memory usage. A perfectly fine leak hunting approach--as long as you are willing to monitor your operating … Continue reading A Better Way to Find Memory Leaks in OpenSees
Life of OpenSees Pi
This is blog post #314, or $latex 100\pi$ to three sig figs. A more recognizable $latex \pi$-times-a-power-of-10 post than post #31 or post #3. And I'll have to maintain the current pace of post writing into my mid 80s in order to reach post #3141. In the G3 days of OpenSees, the inverse sine function … Continue reading Life of OpenSees Pi
It’s OK to Be Negative
A common question is whether or not OpenSees allows negative tags for nodes, elements, materials, time series, patterns, etc. in a model. The obvious answer is "Don't think, just throw". But the polite answer is "Yes, you can define model objects with negative tags". Below is a minimal example where all tags are negative. import … Continue reading It’s OK to Be Negative
Right, then Left
I don't expect every OpenSees contributor to be an expert coder, but I see some dubious coding more frequently than I should. And when I see questionable coding practices, I will call out the offenses so that maybe, just maybe, someone else will consider leaving the cargo cult. For example, the author of CargoConcrete23 wrote … Continue reading Right, then Left
Pleasing the Compiler
Around the transition from G3 to OpenSees, the Visual Studio (VS) compiler was not fully compliant with the then current ISO C++ standard. There were perhaps many items out of compliance, but the non-compliance that drove us nuts was the scoping rule on variables defined in the initialization statement of for loops. The VS compiler … Continue reading Pleasing the Compiler
Something Like a Double Negative
Double negatives are frowned upon in English, but are acceptable in other languages such as Spanish. For example, "No hay nada" is perfectly fine but may sound odd to native English speakers. Along similar lines, I recently came across some OpenSees code that looked something like this: const int N = 20; double Fx[N]; // … Continue reading Something Like a Double Negative