1NGDOTS(3NCARG) NCAR GRAPHICS NGDOTS(3NCARG)
2
6 NGDOTS - Draws filled circular dots at coordinate positions
7 (X(I),Y(I),I=1,NUM) at size SIZE with color given by the color index
8 ICOLOR.
9
11 CALL NGDOTS(X,Y,NUM,SIZE,ICOLOR)
12
14 #include <ncarg/ncargC.h>
15 void c_ngdots(float *x, float *y, int num, float size,
17 int icolor)
18
20 X (an input array of type REAL) defining the X world
21 coordinates where a sequence of circular filled dots is to
22 be drawn.
23 Y (an input array of type REAL) defining the Y world
25 coordinates where a sequence of circular filled dots is to
26 be drawn.
27 NUM (an input parameter of type INTEGER) the value of which is
29 the number of dots to be drawn.
30 SIZE (an input parameter of type REAL) the value of which is the
32 size, in world coordinate Y-axis units, of the diameter of
33 each dot to be drawn.
34 ICOLOR (an input parameter of type INTEGER) the value of which is
36 the GKS color index specifying what color the dots will be.
37
39 The C binding argument descriptions are the same as the FORTRAN
40 argument descriptions.
41
43 The coordinates must be world coordinates and not user coordinates.
44 NGDOTS does not respect the log scaling or axis reversal options of the
45 SET call and will report a warning if these are not set to their
46 default values.
47 The dots are scaled appropriately so that they will be circular when
49 the normalization transformation does not preserve aspect ratio.
50 The algorithm is to construct a single circle and then translate it to
52 the various coordinate positions. The original circle is computed by
53 using trig functions to get points in the first octant, and then using
54 symmetries to get the rest of the points on the circle.
55 The number of points used for the circle is adjusted depending on the
57 relative size of the circle. The maximum number of points is 512 and
58 the minimum is 8.
59
61 Assuming that normalization transformation 0 is in effect and that
62 color index 2 has been defined as red in a call to GSCR, then
63 CALL NGDOTS(.5,.25,1,.1,2)
65 would draw a single red dot at world coordinate position (.5,.25) with
67 a diameter of .1 .
68 Use the ncargex command to see the following relevant example:
70 fngngdts.
71
73 To use NGDOTS or c_ngdots, load the NCAR Graphics libraries ncarg,
74 ncarg_gks, and ncarg_c, preferably in that order.
75
77 Warning messages will be issued if one calls NGDOTS after having called
78 SET with any final argument other than "1".
79
81 Online: gpm(3NCARG), point(3NCARG), points(3NCARG), set(3NCARG),
82 ncarg_cbind(3NCARG)
83 Online URL: http://ngwww.ucar.edu/ngdoc/ng/gks/gkshome.html
85 Hardcopy: NCAR Graphics Fundamentals, UNIX Version; "The Use of X/Y
87 Coordinates in NCAR Graphics" SCD User Document
88
90 Copyright (C) 1987-2007
91 University Corporation for Atmospheric Research
92 This documentation is free software; you can redistribute it and/or
94 modify it under the terms of the GNU General Public License as
95 published by the Free Software Foundation; either version 2 of the
96 License, or (at your option) any later version.
97 This software is distributed in the hope that it will be useful, but
99 WITHOUT ANY WARRANTY; without even the implied warranty of
100 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
101 General Public License for more details.
102 You should have received a copy of the GNU General Public License along
104 with this software; if not, write to the Free Software Foundation,
105 Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
106UNIX March 1993 NGDOTS(3NCARG)