xml_to_hdf5

When very large experimental files are generated from the biaxial testing machine, it is unable to export as raw data. To alleviate this issue, the present module can read the raw xml file that the biaxial testing machine uses internally to store the testing data. That file can be found in the test folder: e.g. <TestName>/test_runs/<TestRunName>/Data/daqTaskActivity1.xml

xml_to_hdf5.main(argv)[source]
xml_to_hdf5.save_data(file, data, units, dtypes=None, global_attributes=None)[source]

Save data to hdf5 file for later use

Parameters:

  • file (str) – Path to hdf file to save data to, excluding .hdf suffix

  • data (dict) – Data dictionary where each item is a numpy array

  • units (dict) – Dictionary with same keys as data, describing the units of the data

  • dtypes (dict) – Dictionary with the data types with which the data should be saved

  • global_attributes (dict) – Attributes to add the the top level

xml_to_hdf5.join_data(file, subfiles)[source]
xml_to_hdf5.estimate_lines(file)[source]
xml_to_hdf5.get_data(file, max_lines=None, start_line=0)[source]

Get data from the biaxial machine’s raw xml file.

Parameters:

  • file (str) – Path to xml file

  • max_lines (int) – Max “line number” (i.e. datapoints) to read from xml file. Defaults to None, meaning read until the end

  • start_line (int) – Which line (time step number) to start at. Useful to get data in parts for large files.

Returns:

Dictionary with key based on names in the xml file and content as numpy arrays (float64) Dictionary with key based on names in the xml file and content strings with unit description

Return type:

dict, dict

xml_to_hdf5.get_name_and_unit(line)[source]

Get the name and unit of the given signal description. An example line is

<Signal Name="Running Time" InternalName="Running Time" Dimension="time" Unit="sec" />\n

Parameters:

line (str) – The line in the xml file

Returns:

name, unit

Return type:

str, str

xml_to_hdf5.get_data_value(line, dtype)[source]

Get the data value from the line, an example line is

<Value>8.14404296875</Value>\n

Parameters:

  • line (str) – The line in the xml file

  • dtype (type) – The data type to convert to

Returns:

The value in the requested data type

Return type:

dtype

xml_to_hdf5.reduce_data(raw_data, raw_units, save_disp=False, use_tcnt=False, sensor_dtype=<class 'numpy.float32'>, time_accuracy=0.0001, cnt_tol=0.1)[source]

Reduce the amount of data stored by

  1. Choose appropriate datatypes for sensor values

  2. Automatically determine datatype for time column

  3. Not saving displacement/rotation values unless requested

  4. Save only the indices when the counter changes

  5. Join counters unless requested not to

Parameters:

  • raw_data (dict) – The raw data read from the xml file

  • raw_units (dict) – The units corresponding to raw_data

  • save_disp (bool) – Should displacements and rotations be saved? Defaults to False

  • use_tcnt (bool) – Should the torsional counter be included as well?, Defaults to False

  • sensor_dtype (type) – Datatype for sensor values (load,strain and disp/rota)

  • time_accuracy (float) – The minimum time difference that should be stored accurately

  • cnt_tol (float) – The minimum counter change required to detect new count

Returns:

(data, units, dtype) data: New dictionary with keys “forc”, “torq”, “astr”, “tstr”, “disp”, “rota”, “time”, [“cnt” or (“acnt”, “tcnt”)] whichever is available. Note that only the data in the counters are modified, otherwise no conversion from the machine data is performed. units: Unit strings (converted to ascii characters to avoid strange unicode issues) dtype: The datatype with which the data should be stored.

Return type:

(dict, dict, dict)

xml_to_hdf5.str2ascii(raw_str)[source]
xml_to_hdf5.compensate(data, units, outer_diameter, tstr_sign=0)[source]

Compensate data wrt. units, stiffness and cross-talk.

Parameters:

  • data – The data dictionary to be compensated (as returned from reduce_data())

  • units – Dictionary of units (as returned from reduce_data())

  • outer_diameter – The outer diameter of the test bar [mm]

  • tstr_sign – The sign with which to scale the torsional strain in relation to the torque. -1 if extensometer text upside down, 1 otherwise). If 0 (default), try to automatically detect by correlation with the torque.

Returns:

The compensated data dictionary, adjusted units, attributes describing compensation

Return type:

(dict, dict, dict)