source: trunk/tutorial1/nickel6.html @ 930

Last change on this file since 930 was 930, checked in by toby, 11 years ago

rcs:* properties removed

  • Property svn:keywords set to Author Date Revision Id
File size: 4.4 KB
Line 
1<html>
2<head>
3   <title>EXPGUI Tutorial #6</title>
4</head>
5
6<style>
7A:link {text-decoration:none}
8A:vlink {text-decoration:none}
9</style>
10
11<BODY BGCOLOR="#FFFFFF"
12      topmargin="0" leftmargin="0" marginwidth="0" marginheight="0" 
13      text="#000000" link="#0033ff" vlink="#0033ff" alink="#0033ff">
14
15<?
16   include("/var/www/include/navigation.inc");
17   include("/var/www/include/utility.inc");
18?>
19<blockquote>
20
21<CENTER>
22<H1>GSAS Nickel example using EXPGUI (part 6)</H1>
23</CENTER>
24<H1>
256. Plot data using POWPLOT or LIVEPLOT
26</H1>
27At this point in the GSAS tutorial
28program POWPLOT is used to plot the diffraction data. This
29is done in EXPGUI by pressing POWPLOT button in the button bar, or
30by pressing the POWPLOT menu item in either the Powder menu
31or the Graphs menu. The input supplied to POWPLOT and the
32results are the same as what is shown in the menu, so this will
33not be repeated here.
34<P>
35EXPGUI does offer another way to display diffraction data, LIVEPLOT.
36Similar to the way POWPREF was run in the previous step,
37LIVEPLOT can be started by pressing LIVEPLOT button in the button bar,
38or by pressing the LIVEPLOT menu item in the Graphs menu.
39<P>
40<img src="liveplot1.gif" align=left>
41Since no cycles of refinement have been run,
42after LIVEPLOT has generated a blank window, it must be
43triggered to read the POWPREF output by pressing the "Update Plot"
44item in the File menu.
45A plot similar to the one to the left is then displayed.
46<P>
47The contents of the LIVEPLOT window are discussed more fully
48<A HREF="#liveplot">
49below</A>, but
50note that the calculated diffraction intensities are all
51zero at this point, since GENLES
52has not yet been to run to simulate the pattern.
53Likewise the background values have not yet been fit so
54this curve is a poor fit.
55The blue line shows the values of
56obs-calc (diff), offset negatively. The sum of the fixed background
57values plus the fitted background function is shown
58difference
59pattern is
60<BR clear=left><P>
61<img src="liveplot2.gif" align=left>
62Note that the region plotted can be changed by clicking with the left
63mouse button, to outline the region to be shown, as seen to the left.
64When the left mouse button is pressed a second time, the graph is "zoomed in,"
65as is shown below.
66To "zoom out" to the previous region, press the right mouse button.
67<BR clear=left><P>
68<img src="liveplot3.gif">
69<P>
70<img src="liveplot4.gif" align=left>
71Reflection positions can be marked, using the File/Tickmarks menu.
72<BR clear=left><P>
73<img src="liveplot5.gif" align=left>
74Reflection indices can be displayed by pressing the "h" (or "H") key in the
75position of the reflection to be labeled. The size and time before
76the reflection labels are removed is determined by values in the Options/HKL labeling menu.
77<BR clear=left><P>
78<I>Do not exit LIVEPLOT at this time as it will be used again in part 8 of this
79tutorial.</I>
80<a name="liveplot">
81<H4>LIVEPLOT Contents and Options</H1>
82</a>
83Note that the observed data points (obs) are marked with "x" symbols in
84LIVEPLOT.
85This can be changed in the Options/Obs symbol menu. The simulated
86diffraction data based on the crystallographic model (calc) is shown as
87a red line. The lower blue line shows the values of
88obs-calc (diff), offset negatively to avoid overlapping with the previous
89curves. The green line (mostly obscured in this figure) shows the background
90function (bckg). This is the sum of the fixed background
91values (if any) plus the fitted background function (if used).
92The dashed magenta vertical lines denote reflection positions. The color
93and lengths of these lines can be customized using the
94options/Configure Tickmarks menu item, for example, auto placement mode
95creates the more customary short tickmarks placed below the pattern,
96at different heights when more than one phase is present.
97<P>
98There are many other options available in LIVEPLOT in the Options menu. The
99Appearance and location of the tickmarks can be set. The symbol and symbol size
100used for observed data can be selected.
101The X and Y units can be changed to Q or d-space values. Background
102can be subtracted. The legend can be removed from the plot.
103
104<BR clear=left><HR>
105Previous step: <A HREF="nickel5.html">
106Run POWPREF</A>
107<BR>
108Next step: <A HREF="nickel7.html">
109Setup for Least-Squares Refinement</A>
110
111<HR>
112</blockquote>
113<P><font size=-1><A HREF="MAILTO:crystal@NIST.gov?subject=WWW page <?=$PHP_SELF?>">Comments, corrections or questions: crystal@NIST.gov</A></font><BR>
114<font size=-1><? lastmod(); ?> </font>
115<BR>$Revision: 930 $ $Date: 2009-12-04 23:14:35 +0000 (Fri, 04 Dec 2009) $
116</body>
117</html>
Note: See TracBrowser for help on using the repository browser.