-October 11, 2002: Posted PAN distribution and documentation to web site.
-October 12, 2002: Added capability to print screen, EISF, and parameter group dependence to a JPEG file.
-October 14, 2002: Made minor modifications. Default PS and JPEG filenames are the names of the data files. Fixed minor bug in updating the curve selection slider control. Autoscaling axes now takes into account range including error bars. Now (3-column) ascii files written out using the parameter group dependence utility and EISF utility can be read back into PAN for analysis. -October 15, 2002: Made major change to handling fit interrupts based on a suggestion by Craig Markwardt resulting in a substantial increase in the fit speed. Also removed option to view the fits during an iteration suggested by NCNR users. -October 18, 2002: Added ability to log your results into an HTML file. This is an undocumented feature but this functionality will be discussed in the documentation soon. Also fixed a bug associated with reading in 3-column ascii data after having analyzed grouped data. -October 21, 2002: Users can now save and restore user-defined fit function expressions. Also added feature allowing user to rebin data. Documentation (on-line and PDF) for HTML session log added. -October 31, 2002: Trimmed unnecessary code and removed unnecessary files. -November 4, 2002: Fixed a bug found when adding a user-defined function. -November 15, 2002: PAN receives an honorable mention in RSI code contest. -January 28, 2003: Now PAN can read in tab-delimited ascii files. -August 20, 2003: Added capability to visualize fit parameter correlations. -May 11, 2005: Added capability to perform bootstrap Monte-Carlo error estimate.
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How do I get PAN to read in my data?
Your data can come in two varieties in which PAN will read it: (a) single group or (b) multiple groups
(a). 3-column tab- or space- delimited: x,z,zerr where x is the independent variable, z is the dependent variable, and zerr is the measurement error in the dependent variable.
Example: Simple data set consisting of x, z and zerr
0.000 1.000 1.000
2.000 4.000 2.000
6.000 9.000 3.000
(b). Grouped ASCII data: x,y,z,zerr where x and y are the independent variables, z is the dependent variable, and zerr is the measurement error in the dependent variable.
All lines that begin with a hash # are comment lines and are ignored by PAN. PAN expects the first number to appear without a hash mark to be the number of x values and the second without a hash to be the number of y values. The y values follow next and then two columns of z and zerr grouped by their y value.
Example: In this example we have 5 xvalues and 3 yvalues resulting in 15 total data (z) points. The value of z at x=-2.0 and y=1.0 is 200. The corresponding error, zerr, is 14.1.
# Number of x-values
# Number of y-values
# Group: 0
# Group: 1
# Group: 2
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In order to run PAN you must first download the PAN distribution (393 kb) and unzip it onto your computer. Wherever you unzip it, make sure that the new folders created on your computer are in your IDL path. Next type PAN at the IDL command prompt.
Download PAN source code and associated files (zipped-438 kb)
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This programming effort was done primarily for DAVE, the Data Analysis and Visualization Environment, which is a software package developed at the NIST Center for Neutron Research for the reduction, visualization, and analysis of inelastic neutron scattering data. This work is based upon activities supported by the National Science Foundation under Agreement No. DMR-0086210.
I would like to acknowledge valuable contributions from David Fanning, Craig Markwardt, Ronn Kling, Mark Piper, and Michael D. Galloy. I would also like to acknowledge valuable feedback on this software from David Fanning, Zema Chowdhuri, Jeff Lynn, Matt Woodward, Paul Sokol, Alan Munter, Sungil Park, John Copley, Richard Azuah, Dan Neumann, Craig Brown, and the many users at the NIST Center for Neutron Research.
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This software is provided as is without any warranty whatsoever. Permission to use, copy, modify, and distribute modified or unmodified copies is granted, provided this disclaimer is included unchanged.
PAN written by
Back to topRob Dimeo
NIST Center for Neutron Research
100 Bureau Drive, Stop 8562
Gaithersburg, MD 20899