source: trunk/SRC/Documentation/idldoc_assistant_output/Computation/div.html @ 402

Last change on this file since 402 was 402, checked in by smasson, 15 years ago

update documentation
File size: 6.0 KB
Line 
1
2
3<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
4  <head>
5    <title>div.pro (SAXO Documentation Assistant)</title>
6  </head>
7
8  <body text="#000000" bgcolor="#FFFFFF">
9
10   
11<!-- Navbar template takes a structure with the following fields:
12       overview_href :
13       overview_selected :
14       dir_overview_href :
15       dir_overview_selected :
16       categories_href :
17       categories_selected :
18       index_href :
19       index_selected :
20       search_href :
21       search_selected :
22       file_selected :
23       source_href :
24       source_selected :
25       help_href :
26       help_selected :
27       etc_selected :
28
29       prev_file_href :
30       next_file_href :
31
32       view_single_page_href :
33       view_frames_href :
34
35       summary_fields_href :
36       summary_routine_href :
37       details_routine_href :
38
39       title :
40       subtitle :
41       user :
42-->
43
44
45<table border="0" cellpadding="0" cellspacing="0" width="98%" bgcolor="#F0F0FF" valign="bottom">
46  <tr>
47    <td width="10%">
48<a href="curl.html"><img src="./../prev.gif" border="0" alt="Previous"></a></td>
49    <td width="80%" align="center" valign="center">
50<font size=-1><i>SAXO Documentation Assistant</i>: <a href="./../home.html">Overview</a></font></td>
51    <td width="10%" align="right">
52<a href="grad.html"><img src="./../next.gif" border="0" alt="Next"></a></td>
53  </tr>
54</table>
55
56
57    <h1><font size="-2">Computation/</font></h1>
58    <h2>div.pro</h2>
59
60    <dl>
61    </dl>
62
63   
64 compute the horizontal divergence of a vectors field located on Arakawa C-grid.
65
66
67   
68
69     
70      <a name="#_div"></a>
71
72      <h2>div  <font size="-1" color="#006633">
73 Calculation
74</font></h2>
75
76      <p><font face="Courier"><i>result = </i>div(<i><a href="#_div_keyword_uu">uu</a>, <a href="#_div_keyword_vv">vv</a></i>, <a href="#_div_keyword_DIREC">DIREC</a>=<i>scalar string</i>, <a href="#_div_keyword_MILLION">MILLION</a>=<i>scalar: 0 or 1</i>, <a href="#_div_keyword__EXTRA">_EXTRA</a>=<i>_EXTRA</i>)</font></p>
77
78   
79
80
81    <h3>Return value</h3>
82 the divergence of the input data (with the same size) located at T
83point (see restrictions).
84
85
86   
87    <h3>Parameters</h3>
88   
89
90    <a name="#_div_keyword_uu"></a>
91    <h4>uu&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
92     
93     
94     
95     
96     
97     
98     
99     
100    </h4>
101
102   
103 Matrix representing the zonal coordinates (at U point) of a field of vectors
104 A 2D (xy), 3D (xyz or yt) or a structure readable by <a href="..//ToBeReviewed/LECTURE/litchamp.html">litchamp</a> and containing
105 a 2D (xy), 3D (xyz or yt) array (4D case is not coded yet).
106 note that the dimension of the array must suit the domain dimension.
107
108   
109
110    <a name="#_div_keyword_vv"></a>
111    <h4>vv&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
112     
113     
114     
115     
116     
117     
118     
119     
120    </h4>
121
122   
123 Matrix representing the meridional coordinates (at V point) of a field of vectors
124 A 2D (xy), 3D (xyz or yt) or a structure readable by <a href="..//ToBeReviewed/LECTURE/litchamp.html">litchamp</a> and containing
125 a 2D (xy), 3D (xyz or yt) array (4D case is not coded yet).
126 note that the dimension of the array must suit the domain dimension.
127
128   
129   
130
131   
132    <h3>Keywords</h3>
133
134   
135    <a name="#_div_keyword_DIREC"></a>
136    <h4>DIREC&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
137     
138     
139     
140     
141     
142      <font size="-1" color="#006633">type:</font> <font size="-1" color="#006633"><i>scalar string</i></font>
143     
144     
145    </h4>
146
147   
148 Use if you want to call <a href="..//ToBeReviewed/CALCULS/moyenne.html">moyenne</a> or
149 <a href="..//ToBeReviewed/CALCULS/grossemoyenne.html">grossemoyenne</a> after the div computation
150 (stupid ?) with a mean done in the DIREC direction
151
152   
153    <a name="#_div_keyword_MILLION"></a>
154    <h4>MILLION&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
155     
156     
157     
158     
159     
160      <font size="-1" color="#006633">type:</font> <font size="-1" color="#006633"><i>scalar: 0 or 1</i></font>
161      <font size="-1" color="#006633">default:</font> <font size="-1" color="#006633"><i>0</i></font>
162     
163    </h4>
164
165   
166 Activate to multiply returned array by 1.e6
167 
168   
169    <a name="#_div_keyword__EXTRA"></a>
170    <h4>_EXTRA&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
171     
172     
173     
174     
175     
176     
177     
178     
179    </h4>
180
181   
182 Used to declare that this routine accepts inherited keywords
183
184   
185   
186
187    <h3>Examples</h3><pre>
188
189   IDL> @tst_initorca2
190   IDL> plt, div(dist(jpi,jpj), dist(jpi,jpj))
191
192    </pre><h3>Version history</h3>
193   
194    <h4>Version</h4>
195 $Id: div.pro 378 2008-08-12 12:35:46Z pinsard $
196
197    <h4>History</h4>
198 Guillaume Roullet (grlod@ipsl.jussieu.fr): creation; spring 1998
199 Sebastien Masson (smasson@lodyc.jussieu.fr)
200 adaptation to work with a reduce domain; 12/1/2000
201
202   
203
204    <h3>Known issues</h3>
205   
206   
207    <h4>Todo items</h4>
208 code the 4D case
209
210    <h4>Restrictions</h4>
211
212 - Works only for Arakawa C-grid.
213 - UU must be on U grid, VV must be on V grid
214 - 4D case is not coded yet
215 - the common variable jpt is used to differ xyz (jpt=1) and xyt (jpt=1) cases.
216 - U and V arrays are cut in the same geographic domain. Because of the shift between
217   T, U, V and F grids, it is possible that these two arrays do not have the same
218   size and refer to different indexes. In this case, arrays are re-cut on
219   common indexes. To avoid these re-cuts, use the keyword /memeindice in
220 <a href="..//ToBeReviewed/GRILLE/domdef.html">domdef</a>
221 - When computing the divergence, we update, vargrid, varname, varunits and the
222   grid position parameters (firstxt, lastxt, nxt, firstyt, lastyt, nyt).
223 - points that cannot be computed (domain boundaries, coastline) are set to NaN
224
225
226    <h3>Other attributes</h3>
227   
228   
229    <h4>Uses routines</h4>
230 <a href="..//Commons/cm_4cal.html">cm_4cal</a>
231 <a href="..//Commons/cm_4data.html">cm_4data</a>
232 <a href="..//Commons/cm_4mesh.html">cm_4mesh</a>
233
234   
235   
236   
237
238    <font size="-3"><p>&nbsp;</p></font>
239    <hr size="1" color="#CCCCCC"/>
240     
241
242   
243
244    <p><font color="gray" size="-3">&nbsp;&nbsp;Produced by IDLdoc 2.0.</font></p>
245
246  </body>
247</html>
Note: See TracBrowser for help on using the repository browser.