AixACCT Data Import

Introduction

Ferro implements functions to directly convert data exported from an aixACCT brand ferroelectric tester as a .dat file into the SampleData object format used by the package. This is currently implemented for hysteresis and leakage current measurements, although it has been implemented in a way that other measurement types could easily be imported if SampleData instances were created for them.

In order to read aixACCT TF-x000 tester data into Ferro, it must first be exported as text using the “Export as ASCII” file menu option. This will save a .dat file to disk, which can be parsed by the ferro commands in the aixACCT module as follows:

from ferro import aixacct

my_tf_data = r'/Path/to/my/file/here.dat'
data_dict = aixacct.read_tfdata(my_tf_data)
loaded_SampleData_obj_list = aixacct.load_tfdata(data_dict)

The data_dict in the above code contains all of the information contained in the original .dat file, excluding the summary table at the top of the document. The structure of the dictionary is as follows:

'here.dat':
    'meastype': MeasEnum.HYSTERESIS,
    'datatables':
        'Table 1':
            'metadata':
                Waveform: triangle
                SampleName: RTWhiteB
                Area [mm2]: 0.01
                Thickness [nm]: 255
                ...
            'data':
                '0.000000e+000\t3.235215e-004\t ...'
        'Table 2':
            'metadata':
                Waveform: triangle
                SampleName: RTWhiteB
                Area [mm2]: 0.01
                Thickness [nm]: 255
                ...
            'data':
                '0.000000e+000\t3.235215e-004\t ...'
            ...

One can query data in this structure using standard python dictionary syntax such as:

>>>data_dict['here.dat']['datatables']['Table 1']['metadata']['SampleName']
'RTWhiteB'

The load_tfdata function then takes this dict and loads the relevant parameters from each present data table into a corresponding SampleData object and returns all tables from the file as a list. From here, one can access individual data tables in the list for analysis or loop over the list to perform operations on each measurement.

Functions

class ferro.aixacct.MeasEnum

An Enumeration representing measurement data type.

Valid entries include:

  • HYSTERESIS = 1 (Hysteresis and FORC)
  • FATIGUE = 2
  • PULSE = 3 (PUND)
  • LEAKAGE = 4 (I-V)
ferro.aixacct.check_datatype(filepath)
Parameters:filepath (str) – Full path to file to open.
Returns:MeasEnum.Type – An entry in MeasEnum representing the type of measurement in the file.
Return type:Enum
ferro.aixacct.check_istable(line, datatype)
Parameters:
  • line (str) – Current line in the data file that is open.
  • datatype (MeasEnum) – Type of measurement being read.
Returns:

bool(m) – Boolean representi if the current line is a datatable header or not.
Return type:

boolean
ferro.aixacct.get_multiplier(datatype, key)

Checks to see if unit conversion is defined for current information being parsed.

Parameters:
  • datatype (MeasEnum) – Type of measurement data being converted.
  • key – Current parameters being read from datatable or metadata
Returns:

multiplier – The multiplier needed to read in data values in CGS units.
Return type:

float
ferro.aixacct.load_tfdata(table_dict)
Parameters:table_dict (dict) – A dictionary representing the data parsed from the .dat file by read_tfdata().
Returns:obj_list – A list of SampleData objects of the appropriate type to match the MeasEnum value for the file.
Return type:list
ferro.aixacct.read_tfdata(filepath)

Read an AixACCT .dat text file

Returns data in a dictionary of following structure :
filename:

‘meastype’: MeasEnum.HYSTERESIS, ‘datatables’:

‘Table #’:
‘metadata’:
Waveform: triangle SampleName: RTWhiteB Area [mm2]: 0.01 Thickness [nm]: 255 …
‘data’:
‘0.000000e+000 3.235215e-004 …’
Parameters:filepath (str) – Path (inc. filename) of data to parse
Returns:table_dict – Dictionary containing parsed text file.
Return type:dict