Meta Data

Meta data is important information that is not directly captured from a measurement but can rather be thought of as a snapshot of experiment equipment, capturing operation conditions at data collection. Such meta data can be extremly beneficial in post-processing as it serves as detailed log which measurement operation has been performed in which experimental environment.

Meta Data Plot

Plot of the meta data capturing the sample stage position over time (scan numbers).

Given that multiple scans are stored per file, we can plot meta data as a function of scan number

bl = LoadBeamline()
bl.load(config,'Filename.h5','path to variable')
bl.plot()

  1. Create “Loader” object

  2. Enter the file name of the scan to analyse (‘FileName.h5’) and configuration

  3. Options for path to variable quantities include:

  • All directory paths within the specified h5 file

Spreadsheet/Logbook

Example of an experiment log book.

df = LoadLog()
df.load(config,'Filename.h5',columns,average=True)
df.show() # Shows the log (data frame) interactively
df.export('filename.csv') # export to csv

  1. Create “Loader” object

  2. Enter the file name of the scan to analyse (‘FileName.h5’) and configuration

  3. Options for columns quantities include:

  • Custom dictionary with column headers and quantities, see example below:

columns = dict()

columns['Command'] = 'command'
columns['Sample Stage (ssh)'] = 'Endstation/Motors/ssh'
columns['Sample Stage (ssv)'] = 'Endstation/Motors/ssv'
columns['Sample Stage (ssd)'] = 'Endstation/Motors/ssd'
columns['Spectrometer (XES dist)'] = 'Endstation/Motors/spd'
columns['Spectrometer (XES angl)'] = 'Endstation/Motors/spa'
columns['Flux 4-Jaw (mm)'] = 'Beamline/Apertures/4-Jaw_2/horz_gap'
columns['Mono Grating'] = '/Beamline/Monochromator/grating'
columns['Mono Mirror'] = '/Beamline/Monochromator/mirror'
columns['Polarization'] = 'Beamline/Source/EPU/Polarization'
columns['Status'] = 'status'

Multiple meta data items may be combined as tuples, i.e. (‘comment1’,’comment2’), and get added as one column to the log Rounding may be applied to numbers, i.e. [‘/path/to/item’,int] where int stands for the number of decimal places

  1. Specify average boolean

  • If False, return all data (even if 1d array)

  • If True, return average of 1d array where applicable