NeXpy Example Files¶
The following files are included in the NeXpy distribution and may be accessed from the Help menu or downloaded from the Github repository.
Example data¶
About these example data files¶
These files are examples of data files that may be read by NeXpy.
file |
type |
description |
|---|---|---|
example.nxs |
NeXus HDF5 |
2-D NeXus sine wave example |
chopper.nxs |
NeXus HDF5 |
2-D time-of-flight neutron chopper spectrometer |
Example plugins¶
About the example plugin¶
This contains an example of a package, chopper_plugin that provides
a plugin menu to NeXpy. The entire directory can be copied to another
location to form the template of another plugin, which should be given a
unique name.
The package has an example pyproject.toml file, which defines the
name of the package and an entry point labelled nexpy.plugins, which
allows NeXpy to discover the plugin when the package has been installed,
using python -m pip install ..
Alternatively, the chopper sub-directory could be installed either
locally or within the installed NeXpy package using the Install
Plugin... dialog. However, installing the plugin as an external
package with an entry point is now the preferred method for making the
plugin discoverable.
In this example, a menu item, ‘Chopper’, is added to the top-level NeXpy
menu, with two sub-menu items designed to operated on chopper.nxs,
which is included as an example file. When loaded, select the
chopper root in the NeXpy tree before clicking on either menu item.
The requirement for a plugin is that a function plugin_menu
initializes the submenu items in the package’s __init__.py. These
would normally initiate dialog boxes that are defined within files in
the package, although they could also be imported from an external
package.
get_ei
A simple GUI to calibrate the incident energy by determining the first moments of two monitor peaks and computing the energy from the time difference. The NeXus root must be selected and unlocked so that the calibrated energy can be saved to the NXmonochromator group.
convert_qe
A simple GUI to convert inelastic neutron scattering data in
chopper.nxs from angular and time-of-flight coordinates into Q and
energy transfer. After choosing Q and energy bin sizes, the converted
data can be plotted and/or saved as a new NXdata group within the NeXus
root.
Example scripts¶
About these example scripts¶
These files are examples of scripts that can be run from the script editor within NeXpy. If they are copied to ~/.nexpy/scripts, they can be opened directly from the Scripts Menu.
example.py
A simple script to create a NeXus tree containing a two-dimensional function of NumPy arrays. A similar example is given in the NeXpy documentation.
chopper_plot.py
A script to plot a sequence of cuts, displaced along the y-axis. It assumes
that chopper.nxs, which is one of the example files, has been loaded.