1VELVEC(3NCARG) NCAR GRAPHICS VELVEC(3NCARG)
2
6 VELVEC - A older version of the Vectors utility, now a front-end to
7 VELVCT. It is identical to the VELVCT call except that there is no
8 LENGTH parameter to allow adjustment of the realized length of the
9 maximum vector magnitude.
10
12 VELVEC (U,LU,V,LV,M,N,FLO,HI,NSET,ISPV,SPV)
13
15 VELVEC is obsolete, and is supported only to provide compatibility with
16 old NCAR Graphics codes. However, the compatibility mode parameter,
17 CPM, offers a number of options to help ease the the transition to the
18 new version of the utility. When writing new code you are encouraged
19 not to use this entry point, since it provides less capability than the
20 standard Vectors interface, and may eventually be phased out.
21
23 #include <ncarg/ncargC.h>
24 void c_velvec(float *u, int lu, float *v, int lv, int m,
26 int n, float flo, float hi, int nset,
27 int ispv, float *spv)
28
30 U (REAL 2-dimensional array, dimensioned LU x n: n >= N,
31 input): By default, assumed to contain the first
32 dimensional Cartesian components of the vector field.
33 However, if PLR is non-zero, it is treated as containing
34 the vector magnitudes.
35 LU (INTEGER, input): Actual value of the first dimension of
37 array U.
38 V (REAL 2-dimensional array, dimensioned LV x n: n >= N,
40 input): By default, assumed to contain the second
41 dimensional Cartesian components of the vector field.
42 However, if PLR is non-zero, it is treated as containing
43 the vector angles.
44 LV LV (INTEGER, input): Actual value of the first dimension of
46 array V.
47 M (INTEGER, input): Number of contiguous elements along the
49 first dimensional axis containing data to be processed in
50 each of the arrays, U and V.
51 N (INTEGER, input): Number of contiguous elements along the
53 second dimensional axis containing data to be processed in
54 each of the arrays, U and V.
55 FLO (REAL, input): Minimum vector magnitude allowed to be
57 displayed in the plot.
58 HI (REAL, input): Maximum vector magnitude allowed to be
60 displayed in the plot. If set to 0.0 there is no upper
61 limit imposed.
62 NSET (INTEGER, input): Flag that controls how and when the SET
64 call is invoked. If NSET is 0, VELVEC makes a SET call to
65 establish a standard viewport and window boundaries
66 coincident with the array coordinate boundaries. PERIM is
67 called to draw a border. If NSET is greater than zero,
68 VELVEC does not call SET or PERIM. If NSET is less than
69 zero, VELVEC calls SET to establish window boundaries
70 coincident with the array grid coordinate boundaries but
71 does not modify the viewport or call PERIM. Unlike the
72 VVINIT/VVECTR interface, when VELVEC does a SET call, it
73 always restores the original coordinate system state before
74 returning.
75 ISPV (INTEGER, input): Flag to control the special value
77 feature. 0 means that the feature is not in use. 1 means
78 that if the value of U(I,J)=SPV(1) the vector will not be
79 plotted. 2 means that if the value of V(I,J)=SPV(2) the
80 vector will not be plotted. 3 means that if either
81 U(I,J)=SPV(1) or V(I,J)=SPV(2) then the vector will not be
82 plotted. 4 means that if U(I,J)=SPV(1) and V(I,J)=SPV(2),
83 the vector will not be plotted.
84 SPV (REAL array, dimensioned 2, input): An array of length 2
86 which gives the value in the U array and the value in the V
87 array which denote special values. This argument is ignored
88 if ISPV=0. The default values are 1.0E12.
89
91 The C-binding argument descriptions are the same as the FORTRAN
92 argument descriptions with the following exceptions:
93 lu The second dimension of u in the calling program.
96 lv The second dimension of v in the calling program.
98 m Number of contiguous elements along the second dimensional
100 axis containing data to be processed in each of the arrays,
101 u and v.
102 n Number of contiguous elements along the first dimensional
104 axis containing data to be processed in each of the arrays,
105 u and v.
106
108 VELVEC is used identically to VELVCT except that there is no provision
109 for adjusting the realized length of the maximum vector magnitude. See
110 the velvct man page for more information.
111
113 To use VELVEC or c_velvec, load the NCAR Graphics libraries ncarg,
114 ncarg_gks, and ncarg_c, preferably in that order.
115
117 Online: vectors, vectors_params, fx, vvectr, vvgetc, vvgeti, vvgetr,
118 vvinit, vvrset, vvsetc, vvseti, vvsetr, vvudmv, vvumxy, ncarg_cbind.
119
121 Copyright (C) 1987-2007
122 University Corporation for Atmospheric Research
123 This documentation is free software; you can redistribute it and/or
125 modify it under the terms of the GNU General Public License as
126 published by the Free Software Foundation; either version 2 of the
127 License, or (at your option) any later version.
128 This software is distributed in the hope that it will be useful, but
130 WITHOUT ANY WARRANTY; without even the implied warranty of
131 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
132 General Public License for more details.
133 You should have received a copy of the GNU General Public License along
135 with this software; if not, write to the Free Software Foundation,
136 Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
137UNIX April 1993 VELVEC(3NCARG)