Grapa

DOI: 10.5281/zenodo.1164571

Description

Grapa is a python package providing a graphical interface and the underlying code dedicated to the visualization, analysis and presentation of scientific data, with a focus on photovoltaic research.

A wide range of data formats can loaded by default. The produced graphs are saved both as graphical objects and as text files for later modifications.

The data analysis functions currently focus on photovoltaics and semiconductor material science. Advanced analysis or fitting functions are notably provided for the following characterization techniques: EQE, JV, C-V, C-f, TRPL, SIMS, reflectance, transmittance (not comprehensive list).

The software has extended capabilities for advanced plotting including subplots and insets, and can be used for creating high-quality figures for scientific publications.

Last, the user can add to the software and to the graphical interface his own specific data loading functions as well new data types and analysis functions, with no modification of the existing code.

Grapa stands for "GRAphing and Photovoltaics Analysis".

Cheers!

Features overview

• Open and merge a wide range of experimental data. Data import possible from clipboard.
• Graphical data presentation and graph customisation.
• Graph export in various file formats with user-defined dpi. Additionally create a .txt file containing the raw data for later modifications.
• The supported image formats are the one supported by the savefig function of matplotlib. .emf is also supported, provided a path to an inkscape executable is provided in the config.txt file.
• Drop-down menu to switch between data-relevant views (e.g. log-view for JV data, Tauc plot for EQE)
• Drop-down menu to switch between linear or logarithmic data visualisation.
• A data picker allows selecting and storing chosen data points.
• Can colorize a graph using color gradients.
• Some data types can be fitted. The parameters of the fitted curves can be modified afterwards.
• Data can be loaded from other files or from clipboard, then converted to the desired data type to benefit from data visualisation and processing and fitting options.

Installation

There are several options to install grapa. The easiest is certainly:

pip install grapa

Alternatively, the source can be retrieved from the development page on github (https://github.com/carronr/grapa). Download the latest release and place its content in a folder named “grapa” somewhere on your hard drive, and can be run with your favorite python distribution.

The software graphical user interface GUI can be started by executing the following lines:

import grapa

grapa.grapa()

Grapa can also be used in scripts. Just above the console, a checkbox "Commands in console" should help you to get started.

Grapa was developed using python 3.4 and matplotlib 1.5, and should be compatible with more recent versions.

More questions?

See manual.pdf in folder /manual

Author: Romain Carron (Empa, Laboratory for Thin Films and Photovoltaics)