magmeas

Python module enabling the import and handling of VSM-data acquired on a Quantum Design PPMS/DynaCool/Versalab measurement system.

Description	Badge
Documentation
Tests
Releases
License
DOI

Installation

Just install from PyPI:

pip install magmeas

Usage

Input file formatting

For conveniently importing automatically, make sure that the necessary sample properties are given in the .DAT file. The formatting is as follows:

INFO,m,SAMPLE_MASS
INFO,(a, b, c),SAMPLE_SIZE

With m being the sample mass in mg, a and b being the sample dimensions perpendicular to the magnetization axis and c being the sample dimension parallel to the magnetization axis. So far only cuboid samples are supported and the density is assumed to be m / (a * b * c)

Python

There are four distinct classes that conveniently handle specific types of measurement data:

• VSM: general for all types of VSM measurements
• MH: for all M(H) measurements, still quite unspecific
• MH_major: for major hysteresis loop measurements
• MT: for M(T) measurements

Here is what each of them do at initialisation or automatically with a method:

	VSM	MH	MH_major	MT
import measurement data from Quantum Design .DAT file	✅	✅	✅	✅
export measurement data to csv/yml/hdf5	✅	✅	✅	✅
plotting	❌	✅	✅	✅
calculate properties	❌	❌	✅ $H_c$, $M_r$, $BH_{max}$, $H_k$, S, $M_s$ (optional)	✅ $T_c$
export properties to csv/yml/hdf5	❌	❌	✅	✅

Experimental support for Recoil-loop- and FORC-measurements is also provided in their respective classes. All classes inherit from the EntityCollection class in mammos-entity, using its io functionality. In doing so, they can conveniently be added to a new EntityCollection with magmeas.to_batch, benefitting from the nested structure in these objects even for data export. Plotting of the above highlighted classes is very flexible. Common keyword arguments used in matplotlibs functions can be used. VSM-derived objects can either be plotted to pre-existing matplotlib figures and axes, or they dynamically generate new ones and return them for subsequent formatting.

Documentation is mainly available in the form of detailed docstrings. Just use dir(magmeas) and help(magmeas.VSM) or similar to get more information.

Requires Python >= 3.11 due to dependencies