BigPlanet Documentation

BigPlanet is software to compress a large number of VPLanet simulations for long-term storage and rapid data analysis. It has been designed to work in conjunction with the VSPACE and multi-planet scripts that generate a set of initial conditions files and perform the simulations across multiple cores, respectively.

BigPlanet has three primary use cases: 1) To compress an entire suite of VPLanet runs into a single “BigPlanet archive” for long-term storage, 2) to extract a subset of data into a “BigPlanet file” for rapid analyses, and 3) for use in a python script for plotting with matplotlib.

BigPlanet compresses your parameter sweep into a formatted HDF5 file that can be 50% smaller than the raw data. This file is called a BigPlanet archive and typically has the extension .bpa. As a BigPlanet archive contains all the data from your parameter sweep, you can safely delete the raw data once the archive is created. Note that BigPlanet will also create an MD5 checksum file that monitors the integrity of the archive. Accessing data from the archive is at least 10 times faster than from the raw ASCII text data.

While it is possible to perform analyses and plot outputs from the archive, it is often still painfully slow for parameter sweeps consisting of 10,000 simulations or more. Thus, BigPlanet can also create BigPlanet files, typically with extension .bpf, that contain much smaller subsets of the data. BigPlanet files can also contain statistics of a simulation, such as the minimum eccentricity.

For a suite of ~10,000 simulations, it can take 30 minutes or more to build an archive file and 10s of seconds to build a BigPlanet file. The advantage of BigPlanet is that when it comes time to plot results, reading from a BigPlanet file takes less than 1 second (usually). This speed enables users to quickly develop plotting script to generate publication-worthy figures in a fraction of the time required for the standard approach (opening each relevant file to extract a single parameter from each simulation).

The following links provide more in-depth explanations on how to get the most out of BigPlanet.

Note

To maximize BigPlanet’s power, run VSPACE and MultiPlanet -bp to automatically build the BigPlanet archive immediately after the simulations finish. Then create BigPlanet files from the archive as needed, and use BigPlanet’s scripting functions to extract vectors and matrices for plotting, statistical analyses, etc.