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Documentation for Program CMPR
Why use CMPR?
CMPR is a multipurpose program for powder diffraction data that provides the following features:
- Any type of diffraction data may be used
- Read support for many ASCII data formats; more can be added simply & quickly without recompilation
- Write support for a few ASCII data formats; more can be added simply & quickly without recompilation
- Multiple datasets may be plotted at one time with easy control over how (color, symbol type...) data are displayed
- Facile zoom capability for easy magnification of sections of datasets.
- WYSIWYG graphics export to GRACE for publication-quality output with ability to add annotations, etc.
- Rescaling data (multipliers & offsets) for visual comparison of data sets
- Data conversion features for comparison of different data types (example: plot synchrotron or TOF data as if collected at Cu K alpha or vice-versa)
X-axis conversions:
- d-space
- Q
- two-theta at arbitrary wavelength
- Change intensity scaling to extract pattern details
Intensity conversions:
- Linear
- Sqrt(I)
- Log(I)
- I/sigma(I)
- I^2/sigma(I)^2
- Weighted addition and subtraction of patterns
- Generate lists of reflection positions, optionally omitting reflections that are not allowed by space group extintions or selected symmetry operation(s).
- Graphically superimpose generated reflection positions on data, optionally omitting or highlighting reflections that are not allowed by space group extintions or selected symmetry operation(s).
- Fit up to 8 diffraction peaks using a single pseudo-Voigt peak shape, optionally using a Finger-Cox-Jephcoat asymmetry correction.
- Smooth, take derivatives & extract peak positions from data (beta software contributed by R. Harlow)
- Interface with ITO, TREOR & DICVOL autoindexing programs; view reflection positions for resulting superimposed on diffraction data.
- Interpolate and add overlapping datasets to form a single scan (beta software contributed by R. Harlow)
- Search for matching entries in the ICDD-JCPDS database, with graphical superposition of peaks on diffraction patterns.
The following sections of this web page describe the various modes within the program. Most sections have links to screen dumps of the GUI with a link marked "View panel" or something similar. The most recent additions are noted with the "new" image, while other changes that have been added in the previous few versions are flagged with this image: .
For installation information, see the CMPR/LOGIC overview.
Mouse shortcuts
Zoom
It is possible to enlarge the size of the plot window by dragging the frame of (the border surrounding) the plot window. The scale of the plot will adapt to show the same range of data, but now expanded to fit in the larger window. It is possible to change scale by "zooming in" and display a smaller region of the data in the plot window by clicking in two opposite corners of the region to be shown with the left mouse button (a left-click) (View before and after examples). Zooming in can be done multiple times. It is also possible to "zoom out" and show the previous view of the data by clicking on the right mouse button (a right-click). Note that in Mac OS X, if you have a traditional Mac one-button mouse, you can simulate the middle mouse button by holding down the "Option" (Alt) button and can simulate the right mouse button by holding down the "Command" (Apple) key.Pressing the "z" or "Z" key (Z for Zoom) allows the zoom to be set manually by entering minimum and maximum values for the x- and y-axes.
Live Cursor
Pressing the "l" or "L" key (L for Live cursor) in the plot window creates a panel below the plot that shows the coordinates of the mouse. Pressing "l" or "L" again, or pressing the "Close cursor display" button causes this panel to be removed.Buffer Selection
Most modes within CMPR display a list of datasets that have been created or read in. I call these in-memory datasets buffers.
- left-click Buffers are selected by clicking on them with the left mouse button
- control-left-click The control and shift keys can be used to modify which buffers are selected. Holding the control key down and clicking the left mouse button causes the buffer to be selected or unselected.
- shift-left-drag Holding the shift key down and dragging the left mouse button across part of the list of buffers causes those buffers to be selected.
- double-left click causes the current buffer(s) to be plotted (can be combined with shift or control).
- triple-left click or a right-click (single) causes all buffers to be selected and plotted. (Mac OS X, use mouse + the "Command" (Apple) key.)
Deleting Buffers
Control-right-click (Mac: control+Command+mouse) causes the selected buffers to be removed from the program file list (not deleted from disk). You are prompted to confirm before any buffers are removed.Reflection Labeling
In the EditCell section of the program, it is possible to label the generated reflection position.
- pressing the "H" key: labels individual reflections (also Shift key+left mouse click)
- pressing the "A" key: labels all reflections (also shift+left double-click)
- pressing the "D" key: deletes all reflection labels (also shift+left-doubleclick). Note that individual reflection labels will be typically be erased automatically after a given number of seconds, as set in the Display options page.
Keyboard Shortcuts
There are a number of shortcuts implemented by pressing keyboard keys. A list of them follows, either upper or lower case may be used. Some of these case will function only in certain sections of CMPR.
in plot window/any panel
in plot window/EditCell panel only
- L -- shows "live" cursor position
- Z -- set zoom scaling manually
- left click -- zoom in
- right click -- zoom out (Mac: Command+click)
in plot window/fit panel only
- shift+left click -- label nearby reflections
- shift+double left click -- label all reflections
- shift+right click -- delete reflection labels (Mac: shift+Command+click)
- H -- label nearby reflections
- A -- label all reflections
- D -- delete reflection labels
in any window/any panel:
- control+double left click -- add peak at current position
- S -- set fit range to current zoom
- F -- scroll the fit region forward
- B -- scroll the fit region backward
- E -- expand the scroll fit region
- P -- define peak position
Also see Buffer Selection tricks
- control+C -- exits the program
- F1 key -- show help on current panel
CMPR Program Sections
CMPR consists of a number of program sections (panels) that are selected using the "notebook tabs" directly below the menu bar.
Read (View panel)
This panel is used to read diffraction data in a number of formats.
To read a file into a buffer, select the format on the right and then select a file on either the window that pops up (Windows) or on the central pane (UNIX). Note that files can be read either by double-clicking (with the left button) on them or by pressing the Open (or Read) button.
After a file has been read, it appears in the plot window and if the legend is active (see the Display options panel) the name appears in the legend. Also see the buffer selection section to see how one or more buffers can be plotted.
It is quite easy to extend CMPR to support additional formats as well. (No compiler is needed). For information on creating a new routine for reading data, see the Customizing section, below.
Write (View panel)
This causes the selected buffer(s) to be written. The box at the top shows the directory where files will be written. Note that forward slash characters (/) are used, even for Win-95 and -NT.
It is quite easy to extend CMPR to support writing additional formats as well. (No compiler is needed). For information on creating a new routine for writing data, see the Customizing section, below.
Plot (View panel or view sample plot)
The plot panel is used to display one or more buffers. To select a single buffer, click on the buffer name. A range of buffers can be selected by dragging with the mouse. Individual buffers can be selected or deselected by holding the control key and clicking on the buffer name. The plot is updated when the "Update Plot" button is pressed or with a mouse double-click.
The "Postscript out" button causes a postscript copy of the plot window to be created. Settings on the Display options panel determine where the file is created or how it is printed.
Plots can be exported to grace, a publication-quality graphics package where the displayed plot can be enchanced and annotated. This works very nicely. Alternately, the information on the plot can be exported as a .CSV (comma separated variable) file that can be read by lots of graphic programs, but it will be up to you to designate the formatting.
This panel is also used to change the way a file is displayed. This is done by selecting the file(s) to be changed and then using the appropriate checkboxes to select the color, line type, symbol type and size. The changes will be made when the "Apply Changes" button is pressed.
Rescale (View panel)
This panel is used to modify the stored values in one or more buffers. One can specify constants to multiply the x and y values and constants to add to the x and y values (addition is done after multiplication).
It is also possible to transform the x and y scales. The x-axis can be transformed between Q, d-space and 2-theta units for an arbitrary wavelength. Intensities (y values) can be transformed to square roots [Sqrt(I)], base 10 logarithms [Log(I)]. The I/sig(I) divides each intensity by its estimated error, providing an estimate of the signal-to-noise and the I2/sig(I)2 mode scales each intensity value so that that estimated error is the square-root of the intensity, thus showing raw counts prior to scaling (or the equivalent). Conversion is done before constants are added or multiplied.
Changes are applied when the "Rescale" button is pressed. If more than one scaling or transformation is applied, the operation is applied to the results from the previous operation. However, if the "Reset previously applied scaling" checkbox is selected, the x and y values are reset to the values that were read in, before any scaling or transformation is done.
Combine (View panel)
The Combine panel is used to create a new buffer set by adding or subtracting up to five other buffers. The buffers must have the same number of data points. No attempt is made to offset buffers, so they must all start (and end) with the same x value.
HKLGEN (View panel)
This panel generates a list of the allowed reflections for a given set of unit cell constants and extinction conditions. It is possible to specify symmetry by space group or by selecting individual translational symmetry operations.
Space groups should be entered as specified in GSAS: Enter the centering condition or cell type (P, R, A, B, C, I or F) and then the symmetry along each appropriate axis, with spaces between each axis. Append a final "R" for rhombohedral settings. Some examples are: "P 1 21/c 1" or "P 21/c" for P21/c and "R 3 m" and "R 3 m R" for the hexagonal and rhombohedral settings of R3m, respectively. If an incorrect space group is entered, no error message is generated, but no extinctions are generated.
Unit cells may be input with either direct or reciprocal cell parameters. The reflections are generated and placed in a separate window when the "Compute" button is pressed. This table can be saved to a disk file by entering a file name and pressing the "Save as" button.
EditCell (View panel or view sample plot)
This panel generates a stick-figure plot of the allowed reflections for a given set of unit cell constants. Reflections can be omitted or highlighted if extinct due to symmetry.
Unit cells may be input with either direct or reciprocal cell parameters. Use of reciprocal cell parameters has proven valuable for indexing powder diffraction data with low symmetry unit cells where some reciprocal unit cell vectors are known from electron diffraction.
Symmetry can be specifed by space group or by selecting individual translational symmetry operations. Space groups are entered as used in GSAS. Enter the centering condition and then the symmetry along each appropriate axis, with spaces between each axis. Append a final "R" for rhombohedral settings. Some examples are: "P 1 21/c 1" or "P 21/c" for P 21/c and "R 3 m" for and "R 3 m R" for the hexagonal and rhombohedral settings of R 3 m, respectively. If an incorrect space group is entered, no error message is generated, but no extinctions are generated.
After the unit cell parameters have been entered and the "Compute" button is pressed, reflections are generated and displayed as a stick figure. At this point list of buffers is then displayed. If symmetry information was entered before the compute button was pressed, the extinct reflections are not included in the reflection list. If symmetry information is entered after the compute button is pressed, the extinct reflections are highlighted in yellow. To superimpose the stick figure on one or more buffers, select the buffers and press "Update Plot" button.
The plot will respond to changes in the unit cell parameters or zero correction made either by typing value(s) into the entry boxes or by sliding the bars to the left of each number. The zero correction is added to two-theta values. Unit cell symmetry can be raised by selecting a higher symmetry cell from the list in the middle. To lower the symmetry, a new peaklist must be created.
To redisplay a previously generated set of reflections, select the appropriate buffer using the "Select peaklist" button in the upper left of the panel. Note that this recenters the unit cell sliders and recomputes the reflections within the requested angular range (see Options).
Individual reflections can be labeled by holding the Shift key and clicking on the reflection position with the left mouse button (shift-left-click). All reflections can be labeled by holding Shift key and double-clicking anywhere in the plot with the left mouse button (shift-left-doubleclick). Individual reflection labels will be typically be erased automatically after a given number of seconds, set in the Options panel; an erase time of 0 means that reflections labels are not automatically erased. Holding the Shift key and clicking anywhere with the right mouse button (shift-right-click) clears labels for all reflections (Mac: Command+shift+mouse). The size of reflection labels can be changed on the Options panel. (see Options).
Note that the size for the reflection markers, with respect to the Y axis, is determined by the "Maximum and Minimum Y values" on the right side of the screen.
In the example images, (View panel or plot), the reflection list was generated using space group R -3 but then space extinctions for R -3c are labeled. Thus, the reflections made extinct by the c-glide are shown in yellow. Reflections extinct in R -3 are not shown.
Fit (View panel or View sample plot)
Fit is used for profile fitting of selected regions of a pattern. Peaks are fit with a pseudo-Voigt where eta is the "mixing term." A value of 0.0 for eta selects a completely Gaussian peak shape and a value of 1.0 selects a completely Lorenztian peak shape.
Once a refinement has been done, the peak positions in the peak list buffer are updated also a "Undo last cycle" button is shown. Pressing this button resets the values in the various boxes to their values from before the refinement (it does not change the values in the peak list buffer). If you want to save the fitted curve, the "Store Fit" button creates a buffer with the current fit result.To fit peaks:
- A buffer to fit is selected using the "Select Dataset" button in the upper left. If only one appropriate dataset is present, it is selected automatically.
- A buffer to record the peak positions is selected. The first peak list (if any) is the default, but it is also possible select "new" which will add peaks to an empty list.
- Select a data range to be fit. The range must contain less than 1000 data points. The range can be set using the mouse to zoom and the S/Z/F/B/E keyboard shortcuts or use the "Set range to fit" submenu. This creates a dialog box (view) to set the data range with three options:
When a range of data is selected, any peaks found in the peakfile in that data range are displayed on the plot and are added to the peak list menu to the right.
- use the mouse to zoom in on a region and press the "Set from zoom" button, or
- type an upper and lower two-theta value in the "Fit Range" boxes, or
- shift the range using an increment and "Add increment to limits" button.
- There are two methods for adding new peaks to the menu:
- by pressing the "P" key (P for Peak) while positioning the mouse to the location of the peak maximum (shift+double-left-click also works)
- by pressing the "set" button in any row of the peak table and then pressing the "P" key, after moving the desired peak maximum. This "set" button can also be used to redefine peaks in the table.
- Select parameters to refine: Once at least one peak has been entered, and a suitable range has been selected, a "Run GPLSFT" button appears. Select the parameters to be refined by clicking on the appropriate boxes to the right of the parameters
- Optimize parameters by pressing the "Run GPLSFT" button. The least-squares algorithm in the program is far from robust. It is wise to first refine the peak areas and FWHM terms and then add background and eta and peak positions after reasonable fits are obtained. If the fit blows uo, refine fewer parameters at a time or decrease the damping value.
The GPLSFT program can use the Finger-Cox-Jephcoat correction for peak asymmetry. For this correction, three terms must be known: the diffractometer radius, the half-height (or half-width) of the sample and of the detector. Values may be specified in any consistent units. (NIST would prefer that you use metric units, of course.) While these values can be refined, do so with care: do not refine too many variables at the same time, use a small number of cycles and set the damping factor to a small number.
By default fit results are shown superimposed on the plot of the fit, but the results can be placed in a separate window by deselecting the "Report fit results in plot window" checkbox on the Options panel.
Peaks/Smooth (View panel)
This panel is used to smooth one or more diffraction patterns with a Gaussian. The smoothed results can be used to compute a first and second derivative of the data as well. Peak positions, as well as height and area estimates can be made using the second derivative. Once the peak positions are determined, sections of data away from the peak positions are used to construct an estimate of the background.
The "FWHM" setting controls the width of the Gaussian convolution function for all of the above computations. It seems that it is best to set this to the approximate FWHM seen for peaks in the data.
The "Sensitivity" and "ESD" settings are used only for peak searching. Both are used to reject peaks below signal-to-noise criteria, but the exact functioning of these settings is not well understood.
This code is still under development and comments and suggestions can be offered to Dick Harlow.
Index (View panel or Results Window)
This page is used to prepare input to three autoinexing programs, ITO, TREOR and DICVOL. These programs attempt to find unit cells that index a set of diffraction peaks.
The list of peaks is compiled into a buffer by using Peaks and/or using Fit (Fit is recommended for the most accurate peak positions). The peak list is then selected with the button on the upper left. A list of peaks is then shown to the right, where it is possible to select which peaks are used for autoindexing. Input files are created for all that are selected via the checkboxes to the left when the "Write file(s) & Run" button is pressed. For each selected program, it is then possible to select that the program be run in "foreground" (CMPR pauses while the run progresses) or in "background" (CMPR continues). Note that values for various program options are provided in the center section of the this page. Defaults values are used for all program options. However, it is possible to override these values from this section. For example, on the index panel example, the maximum cell length allowed by TREOR is increased to 30 Angstrom.
Once any of the programs have been run, the output file can be examined using the "Review Output" button. Two windows are created: the first shows the output file from the indexing program in a scrollable window and the second window shows the unit cells that have been located. Pressing the "Set" button to the left of any cell parameters causes those values to be loaded into EditCell. This allows the unit cell to be compared to an observed diffraction pattern.
Logic (View panel)
This panel provides an interface to the ICDD-JCPDS PDF-2 powder diffraction database, when the database has been installed on the local computer. It provides most of the functionality of the LOGIC program, which is documented elsewhere.
If the database is not installed, the Logic notebook tab will be omitted. (See the ENCODE program for information on installing the database.)
After performing a search, the located entries are shown in the index in the lower section of the panel. Note that the fields shown in the index can be changed using the Logic options/index contents menu command. Double-clicking on an entry in the index will show more information about that entry in a separate window (see Browse in the Logic documentation.) A single mouse click causes an entry to be selected (highlighted). After one or more entries have been highlighted, peak positions can be plotted by pressing the "Read in Selected Entries" button.
Interp (View panel)
This panel was developed primarily by Dick Harlow. It is used to combine and interpolate overlapping datafiles. These routines are still under development, so users should review the output carefully and report problems.
Display options (View panel)
The Options entry on the menu bar is used to change the appearance of the program on your screen. By selecting the "Display Options" menu item, a window is created where many options within the program can be selected, see below. The "Screen Font" menu item can be used to change the sizes of fonts used throughout the program. (See below for information on how to modify the default value for the screen font).
Selecting the "Display Options" menu item opens a window used to set values used in other parts of the program (click here to view). The sections within this window are:
- "Plot options"
- determine how data are displayed and recorded
- "Plot legend" determines if a legend is shown on the right-hand side of the plot.
- "Write PostScript" and "Print PostScript" options determine what is done when the the "PostScript out" button is pressed in sections of the program, such as Fit and Plot.
- If "Write" is selected, a file name is specified as the "Postscript file name".
- If "Print" is selected, a UNIX command for processing the file is specified as the "Command to print files" (this option is not available in Windows).
- "Peak Fit Options"
- are used for the Fit section of the program.
- The "Report fit results in plot window" option controls if the fitted parameters are shown in the plot window or in a separate window.
- "EditCell options"
- are used in the EditCell section of the program.
- "2theta max" determines the maximum hkl value computed by the program
- "max change in cell parameter" controls the range and thus the sensitivity of the sliders
- "HKL label erase time" specifies the number of seconds before reflection labels are erased in seconds. A value of 0 or less means that these labels are not automatically erased.
- "HKL label size" specifies the size of the reflection labels in pixels (or points for negative values).
- "Help Options"
- determine how help information is displayed. Help can be displayed in a browser (Netscape must installed for UNIX systems) or in a help window.
Help (View panel)
Help can be used to find out more about a section of CMPR. Help can be displayed on a web browser or in a separate window, depending on the setting on the options panel. The web help is more complete, but may be more cumbersome.
Help is invoked by pressing the F1 key or using "Help on current page" in the Help section of the menubar. The help is somewhat context-sensitive help as the section of help information relevant to the current panel is displayed.
CMPR is designed to be expanded. Read the code and send me any extensions you create. Have fun!
Customizing
Customization files
CMPR reads options for customization sourcing file localcmds.tcl from the directory where CMPR is installed and then [UNIX] file .cmpr_init from the user's home directory or [Windows] C:\cmpr.init. There are no errors if either or both files do not exist. Various Tcl commands can be placed in this file. One example is:
set graph(font) 18This command overrides the default value for the screen font from 14 point (set in the cmpr.tcl file) to 18 point.
Many other options can be modified in this fashion. Users are referred to the CMPR code to find them and see how they work.
Reading directly from GSAS experiments
The read_gsasexp.tcl file reads diffraction data (observed and computed) as well as reflection positions from the GSAS .EXP, .Pxx and .Rxx files. To do this, it must locate the directory containing the GSAS programs tcldump or hstdmp. This is done by searching the directory defined by environment variable GSAS (if defined) and then sequentially the directory below where cmpr is loaded (../gsas), /usr/local/gsas/exe, c:\gsas\exe and ~/gsas/exe. If you do not see a checkbox labeled "GSAS EXP file" for a file format, define the environment variable GSAS to define the location where GSAS is stored or else you can define tcl variable gsaspath to the location where the GSAS executables are found (for example, set gsaspath c:/NCNRfiles/GSAS/exe) in the localconfig or
Using the Example File Formats
When CMPR is downloaded, there are a fair number of file formats available for use. Some are incorporated by default and others do not appear unless you specifically include them. To access the file formats that are included as "Example_read_*.tcl" files, you need to either rename them to "read_*.tcl", create a link to these files (in UNIX) or specifically cause them to be loaded. Renaming them is simplest, but has the disadvantage that the files will not be updated if you update CMPR.
I recommend creating a reference to the desired files in your localcmds.tcl or ~/.cmpr_init (C:\.cmpr_init) file, as this method works on either platform. Create (or append) to either file a line like this:
source $scriptdir/Example_read_cpi.tclto have the appropriate file format included.Supporting Additional File Formats
To define new formats for reading a file create a file called read_????.tcl where you supply a name of your choice for '????'. Likewise, to support a new output format, create a write_????.tcl file. Note that formats are listed on the menu alphabetically by file name. Follow one of the other read_*.tcl or write_*.tcl files as an example. Place the file in the same directory as the cmpr.tcl file (and the other .tcl files).
Notes on coding a read_????.tcl file
- Define a commandline option to read a file (optional) using command(cmdopt) and defining a routine associated with the command option for example:
lappend command(cmdopt) -xxx set command(-xxx) readxxxdatadefines that commandcmpr.tcl -xxx yyy.xxxcan be used to read file yyy.xxx using read routine readxxxdata (see below)You can define as many options as you want or none, but be sure to define them in pairs, as above. If you don't want to support reading this type of file from the command line, you don't need to include these two statements.
- Define the dialog access define the text to be shown
lappend command(readtypes) "LHPM/RIET7"define a command to read the datalappend command(readproc) ReadLHPMdefine a list of allowed datatype suffixeslappend command(filterlist) {dat}If you will have upper and lower case versions for Unix, you might want to do the following:if {$tcl_platform(platform) == "windows"} { lappend command(filterlist) {dat} } else { lappend command(filterlist) {dat DAT} }Define a datatype listing (not used at present) to describe the suffix:set command(ReadLHPM_dat_type) "LHPM/RIET7 data" set command(ReadLHPM_DAT_type) "LHPM/RIET7 data"Note that the info in parentheses corresponds to the name used for command(readproc) followed by each value used for command(filterlist).- Define a dialog box read routine This almost always looks the same, except for the readXXXXdata line which refers to the real proc used to read the data.
proc ReadLHPM {file} { global command if {$file == ""} return pleasewait "reading file $file" set ret [readLHPMdata $file] donewait if {$ret != ""} {return $ret} showlastentry $command(read_filelist) }- Define a routine to actually read the data. Try to imagine how the routine will crash and burn when a user specifies a data file with the wrong format.
Look at the other read routines to see examples.
The CMPR program will automatically include the new format the next time it is started. Likewise, to remove a format all that need be done is to change the file name so that it starts with something other than read_ or end with something other than .tcl, for example note the files named Example_read_*.tcl.
Notes on coding a write_????.tcl file
- add the format name to command(writetypes) and the procedure name to command(writeproc)
lappend command(writetypes) ".csv (Spreadsheet)" lappend command(writeproc) writelistcsv- Write a proc to write the data/peaks Note that you can use the statement
if {[set ${data}(type)] == "peaks"} {to take different action depending on if a peak file is being written Likewise, you can use the statementif {$command(writeunits) == 0} {to take different action if scaled values or original values should be written.Look at the other write routines to see examples.
The CMPR program will automatically include the new format the next time it is started. Likewise, to remove a format all that need be done is to change the file name so that it starts with something other than write_ or end with something other than .tcl.
grace
Grace (xmgrace) is a nice WYSIWYG 2D plotting tool for X Windows. Many UNIX users will be familiar with a prior version of grace, known as xmgr. It is distributed under the terms of the Free Software Foundation public license, and may be downloaded for free. Grace runs on practically any version of Unix. As well, it has been successfully ported to VMS, OS/2 and Win9*/NT. Use in Windows may be somewhat clumsy, as a X-Windows package is required. See the grace homepage at http://plasma-gate.weizmann.ac.il/Grace/ for more information.I would like to find a Windows program that accepts ASCII input and control files that can be used to generate publication-quality graphics, so that I can generate input files in that format as well.
Neither the author nor the U.S. Government makes any warranty, expressed or implied, or assumes any liability or responsibility for the use of this information or the software described here. Brand names cited here are used for identification purposes and do not constitute an endorsement by NIST.Brian Toby (Brian.Toby@NIST.GOV)
$Revision: 1.9 $ $Date: 2004/12/29 21:19:37 $
Last modified 29-December-2004