mpr files

[merung1203]

I have a question about processing mpr files.

1. def process: module_header_dtype = np.dtype([("short_name", "|S10"), ("long_name", "|S25"), ("length", "<u4"), ("version" , "<u4"), ("date", "|S8")]) in this function, could you explain the purpose of this line?

2. def _process_data: n_datapoints = _read_value(data, 0x0000, "<u4") n_columns = _read_value(data, 0x0004, "|u1") column_ids = _read_values(data, 0x0005, "<u2", n_columns) when I run this code, only the first 21 columns are converted. How can I convert all of the flag_columns and data_columns?

thank you

[vetschn]

Hi! Regarding your first question: The mpr files are made up of a number of modules, each of which starts with a module header that is structured like this:

offset	field name	description
0x0000	short_name	Short name, e.g. VMP Set.
0x000A	long_name	Longer name, e.g. VMP settings.
0x0023	length	Number of bytes in module data.
0x0027	version	Module version.
0x002B	date	Acquisition date in ASCII, e.g. 08/10/21.

With the module_header_dtype you can read all of these values in one go from the binary.

Concerning the second part of your question: Could you provide a file, where you encounter this problem? The parser should parse all data columns stored in the file, not just the first 21.

[merung1203]

Hello! Thank you for your kind reply.

This file is an ec-lab default sample, not an actual analysis file. In fact, in my file, when the mpr file is output as data, the required columns are 'Re(Z)' and '-Im(Z)', but they are not there.

However, when I run the sample file, an error message appears as shown below, so I converted it to data using ec-lab software. I would like to know the code that causes the 'Re(Z)' and '-Im(Z)' columns to appear.

Thank you.

---

ValueError Traceback (most recent call last) in <cell line: 1>() ----> 1 data, meta = ecf.process("./test.mpr")

3 frames /usr/local/lib/python3.10/dist-packages/eclabfiles/mpr.py in _read_value(data, offset, dtype, encoding) 445 # Allow the use of 'pascal' in all of the dtype maps. 446 return _read_pascal_string(data[offset:]) --> 447 value = np.frombuffer(data, offset=offset, dtype=dtype, count=1) 448 item = value.item() 449 if value.dtype.names:

ValueError: offset must be non-negative and no greater than buffer length (1859)

230831 test.zip

[vetschn]

To me it looks like this default sample was created with an older version of EC-Lab (v9.54). I assume the problem is that there is a different offset for the number of parameters in this file version (see here).

This project is only tested on files created with v11.33. In the PEIS mpr files I tested, the Re(Z) and -Im(Z) columns are present and parsed correctly.

If you are using a different version of the software it's pretty much impossible for me to fix, as I don't have access to the equipment. Unfortunately, the people at BioLogic like to randomly change things and do not provide a spec for their binary files.

[PeterKraus]

Yeah, it also fails to parse with the current git of yadg. I'll have a look at it in due course. The mpr format has recently changed again, files from EC-Lab versions newer than (and including) v11.50 also don't work.

@vetschn is there any persistent file version number in the mpr files, or not really?

[maesgeert]

I suffer from the same issue after upgrading the software to v11.50. Any fix would be very welcome! Regards

[vetschn]

Yeah, it also fails to parse with the current git of yadg. I'll have a look at it in due course. The mpr format has recently changed again, files from EC-Lab versions newer than (and including) v11.50 also don't work.

Yep, users over at echemdata/galvani#87 seem to have had problems for a while now as well.

@vetschn is there any persistent file version number in the mpr files, or not really?

The LOG module contains the EC-Lab version (at least for v11.33). However, I don't remember whether the LOG module was present in all the files.

In any case, the most one could do for now would be to raise an exception/warning for unprocessable/untested versions.