Python Libraries from GSECARS

A set of libraries and applications for collecting and working with x-ray data from synchrotrons

Matt Newville, Mark Rivers

Currently supported Python modules developed at CARS:

See also github.com/xraypy and github.com/pyepics for other related projects.

Many of the remaining links here are to work of Mark Rivers from approximately 2001. These modules are not well-supported, and many of these have been replaced by code linked above. We keep thee links for historical purposes.

Plotting Modules

BltPlot	Enhancements to the Pmw.Blt.Graph widget
myTkTop	Workaround for bug in Pmw.Blt.Graph

Mathematics Modules

mpfit	General non-linear least squares data fitting, based on MINPACK
CARSMath	Miscellaneous math functions.
spline	Spline fitting
func	Support module required by spline

General EPICS Modules

epicsPV	Interface to EPICS channel access, enhancements to CaChannel
epicsMotor	Interface to EPICS motor record
epicsScaler	Interface to EPICS scaler record
epicsLogger	GUI application to log EPICS PVs to the screen and to a disk file

Multi-channel Analyzer (MCA) Modules

Mca	Device-independent Multi-Channel Analyzer class
hardwareMca	Virtual class for hardware MCAs, subclass of Mca
epicsMca	EPICS Multi-Channel Analyzer class, subclass of Mca
Med	Device-independent Multi-Element Detector class
epicsMed	EPICS Multi-Element Detector class, subclass of Med
fitPeaks	Fit Gaussian peaks to spectra
jcpds	Powder diffraction lines at high pressure and high temperature
Xrf	Utility functions for X-ray Fluorescence (XRF)
mcaDisplay	GUI for display and control of MCAs. Device-independent.
mcaCalibrateEnergy	GUI to calibrate energy of an MCA
mcaCalibrate2Theta	GUI to calibrate 2-theta of an MCA
mcaControlPresets	GUI to control presets of an MCA
mcaPeakFit	GUI to fit peaks and background of an MCA
medDisplay	GUI for display and control of an epicsMed
localMedLayout	Site-specific module to define geometry of a multi-element detector

Requirements

The above packages require one or more of the following Python packages available elsewhere:

Python	Python 2.2.1. The above packages have been tested with Python 2.1 and 2.2.1. I recommend using 2.2.1 or higher, since future enhancements may require it.
Numpy	Numerical Python
Pmw	Python MegaWidgets for Tkinter
Blt	Plotting toolkit
EPICS support	EPICS support files. Includes Geoff Savage's CaPython and CaChannel, but with pre-built binaries for Python 2.1 and 2.2 on Windows and Linux. Also includes Ezca, another interface to EPICS Channel Access, written by Matt Newville.

Installation on Windows platforms

Fetching and installing the above packages is a bit of a nuisance. Blt requires some messing around to get it to run with Python on Windows. The following is a simple procedure for getting Python 2.2.1 with the above up and running on any Windows machine with all of the above modules.

Download and install Python
Download this zip file. Unzip the file into the top-level Python directory (typically C:\Python22 or C:\Program Files\Python22)
Add the top-level Python directory to your Windows "PATH". On Windows NT this is done with Control Panel/System/Environment. On Windows 2000 and Windows XP it is done with Control Panel/System/Advanced/Environment Variables. Edit the PATH environment variable in the System settings to add C:\Python22 or C:\Program Files\Python22 (or wherever you put Python)
Optionally define the following environment variables using the same technique
You must also have com.dll and ca.dll somewhere in your Windows PATH. You can get these from the EPICS Win32 Extensions, which includes medm. Note that the EPICS Win32 Extensions installation does not put ca.dll and com.dll into your PATH. You will have to do this manually.

PRINT_COMMAND	Command to send a Postscript file to the printer. Used by mcaDisplay and BltPlot. Default = "print ", which will print to default printer. Example: `print /d:\\cars5\GSEFLOOR`
JCPDS_PATH	The path to the JCPDS files. Example: `C:\epics_user\jcpds`
XRF_PEAK_LIBRARY	Path to the file containing XRF fluorescence lines. Example: `C:\epics_user\xrf_peak_library.txt`
MCA_SETTINGS	Location of a file to store preferences for the mcaDisplay program. Example: `C:\epics\mca_settings.dat`
MCA_HELP_COMMAND	Command to start a Web browser with help on the mcaDisplay program. Example: `start http://cars9.uchicago.edu/software/python/mcaDisplay.html`

Suggestions and comments to: Mark Rivers : (rivers@cars.uchicago.edu)
Last modified: September 28, 2002