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An example of using the MeanVsScan Box to plot an average parameter (in this case the width of a distribution) vs. the fly-scanned PV.  "fly - scan" means the scan value is changed independently while the DAQ free-runs.  Compared to a "step scan" (see below) it has the disadvantage that there is no precise knowledge of the scan variable value at each event, since the scan variable is moving during data taking and is only recorded by the DAQ at 1Hz.

ami-local -l /reg/g/psdm/tutorials/ami2/neh2.2/rix_flyscan.fc psana://exp=rixx43518,run=34,dir=/cds/data/psdm/prj/public01/xtc

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Step-Scan With Gaussian Fit

Imperfections that need to be addressed:  the method of detecting that a step has finished (triggering the fit) is kludgy, so the last step is currently ignored.  Pedestal A "step scan" is a mode where the DAQ is paused whenever the scan variable changes.  Unlike a fly-scan, it is possible to assigned each event to a well-defined scan variable value.  These scans are typically controlled by the hutch-python tool, which uses the bluesky tool from BNL.  In this particular example, pedestal subtraction helps the fit significantly and is done in a kludgy way with using /reg/g/psdm/tutorials/ami2/neh2.2/manta_ped.py which generates a numpy pedestal file /reg/g/psdm/tutorials/ami2/neh2.2/manta_ped.npy.  Subtraction  The pedestal subtraction is done with a PythonEditor box.

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