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This wiki contains guides for using OSKAR to run experiments with LabVIEW and to record data using HDF5.

Installation instructions are available in the README.md

Overview

• RID - The timestamp (YYYYmmdd_HHMMSS) that identifies execution of a collection of measurements (an experimental run).
• SQUID - An iterating number used to identify each measurement within an experimental run.
• VARS - The hardware settings that define each measurement, such as laser wavelength = X, applied voltage = Y.
• HDF5 - A flexible, structured file format that is widely used for storing scientific data. There are many freely available libraries for importing hdf5 data for analysis, e.g., h5py for python. HDFView is a useful stand-alone application for opening and exploring HDF5 files.

When a run is started, sequencer.vi reads a json file that stipulates each configuration of VARs that will make up the entire experiment. The first set of VAR values are then distributed to the control hardware and measurements are then recorded for the specified acquisition time. Next, another set of VAR values is sent to the control hardware. The whole process repeats until all measurements have completed.

At the start of the run a HDF5 file is created [YYYY]/[mm]/[dd]/[RID]/[RID]_data.h5. This file is subsequently populated with groups that each correspond to an acquisition period, identified by the SQUID. The groups contain the datasets acquired during each SQUID. Information relating to each SQUID (e.g., the corresponding VAR values) is recorded as group attributes.

The json sequence files (*.jsq) can be written to systematically cover large parameter spaces using modder.vi or scan.vi.