Understanding Keys

Keys are the bread and butter of BigPlanet. The keys are the names of the variables that can be extracted from a BigPlanet archive.

Note

Keys using the following format for naming: body:parameter:aggregation, where “aggregation” is an aspect of the variable.

Below is a table of aggregations related to input and output files:

Aggregation	Description
Initial	The initial values of a parameter as listed in the log file
Final	The final values of a parameter as listed in the log file
Option	The parameter’s argument to an option in the input file
Forward	A list of the parameter’s values in the forward file.
Backward	A list of the parameter’s values in the backward file.
Climate	A list of the parameter’s climate values (POISE only).
OutputOrder	A list of the parameters and units assoicated with saOutputOrder.
GridOutput Order	A list of the names and units of the climate file (POISE only).

In addition, variables that are listed in VPLanet forward or backward files also have a set of statistical aggretations that can be applied. Use one of these to quickly obtain metadata on a particular variable. For example, Earth:Eccentricity:Min would return the minimum values of eccentricity recorded for every simulation.

Aggregation	Description
Min	The minimum values of a parameter recorded for each simulation.
Max	The maximum values of a parameter recorded for each simulation.
Mean	The arithmetic means of a parameter recorded for each simulation.
Geometric Mean	The geometric means of a parameter recorded for each simulation.
Standard Deviation	The standard deviations of a parameter recorded for each simulation.

Warning

The preceding aggregations will only work with parameters that are from the forward or backward file.