The following will make the user familiar with the basic layout and functions of the graphical users interface (GUI) of the trEPR toolbox.

Those who want to make use of the toolbox exclusively on the command line (CLI) will find help in the documentation of each function (to be added soon).

For both groups, users of the GUI and the CLI, a look at the tasks of the toolbox may be of interest. There, the goal is to explain, in a systematic way, the tasks the toolbox (and its GUI) were originally designed for. Besides that, this introduction gives a general overview of the “preprocessing” of transient EPR spectra.

As a start, a few important aspects are listed that should answer more general questions right from the beginning.

• Separation of GUI and data manipulation
  All functions operating on the actual datasets are clearly separated from and independent of the GUI. They can be used in the same way from the Matlab® command line (CLI).
• Dataset as fundamental unit
  The “fundamental unit” of the toolbox (and, therefore, its GUI) is a single dataset. All functions are performed on such a dataset. That means that every measurement is accounted for as a dataset, even though the raw data file may contain several datasets (as in case of fsc2, Berlin) or the dataset may consist of several files (time traces) that need to be combined to a dataaset (as with the Freiburg data).
• Keyboard shortcuts in the GUI
  Keyboard shortcuts for some important functions are integrated and consistently used throughout the whole GUI and its subwindows. Although most tasks can still only be performed using the pointer device (and Matlab® GUIs provide some inherent limitations to keyboard shortcuts), a few functions as switching between the different panels of a GUI window or switching between the different display modes can be reached by keyboard. Details about the keyboard shortcuts can be found in the help included in the GUI.

To start the GUI after you have successfully installed it, is easy: Just type the name of the respective Matlab® function into the Matlab® command window and press return.

trEPRgui;

In case that you already opened a trEPR GUI window previously that is now somewhere in the background, this will get the focus and (re)appear in front of all other windows, rather than opening another GUI window (so-called “singleton” concept: only one instance of the GUI can be opened at a time).

The main GUI window is the central interface between user and toolbox. Here, you can load and display datasets, and from here, you can open additional windows to perform more complicated operations on your datasets.

For a first overview of the GUI and its controls (including lots of screenshots) see the respective documentation.

Generally, extensive help is included into the GUI windows, that can be accessed either the “Help” button in the main GUI window, via the button with the questionmark in all GUI windows, or, for those who prefer the keyboard, via the shortcut “F1”.