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data taking on the lab servers and only having the very low bandwidth control
panel running on the remote machine. The Grapher will then display points as
quickly as it can retrieve them from the Data Vault, potentially reducing the
refresh rate of the plots, but usually not impacting the overall time it takes for an
experiment to complete.
7.5.6 Data Vault
The Data Vault Server Module acts as the central data storage location for
all datasets taken with the LabRAD system. Datasets are stored in a directory
structure and accessed by name, much like a conventional computer file system.
It provides the usual created/last-accessed/last-modified time stamps as well as
other named meta-data that can be stored alongside the data. The data itself
consists of a 2D table of LabRAD “Values” in which each row corresponds to
one data point. The columns contain first the values along the independent axes
followed by the values along the dependent axes. The Data Vault also associates
a message log with each dataset to provide the ability to annotate the data later
using, for example, the Grapher’s chat session.
To allow for the Grapher to
automatically open datasets and to keep directory listings updated, the Data Vault
can send notification messages to other Modules to announce the availability of
new data, etc. The data itself is stored simply as flat files in folders on the local
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