1NGDOTS(3NCARG)                   NCAR GRAPHICS                  NGDOTS(3NCARG)
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NAME

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.
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SYNOPSIS

11       CALL NGDOTS(X,Y,NUM,SIZE,ICOLOR)
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C-BINDING SYNOPSIS

14       #include <ncarg/ncargC.h>
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16       void c_ngdots(float *x, float *y, int num, float size,
17       int icolor)
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DESCRIPTION

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.
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24       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.
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28       NUM         (an input parameter of type INTEGER) the value of which is
29                   the number of dots to be drawn.
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31       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.
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35       ICOLOR      (an input parameter of type INTEGER) the value of which is
36                   the GKS color index specifying what color the dots will be.
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C-BINDING DESCRIPTION

39       The C binding argument descriptions are the same as the FORTRAN
40       argument descriptions.
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USAGE

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.
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48       The dots are scaled appropriately so that they will be circular when
49       the normalization transformation does not preserve aspect ratio.
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51       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.
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56       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.
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EXAMPLES

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
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64               CALL NGDOTS(.5,.25,1,.1,2)
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66       would draw a single red dot at world coordinate position (.5,.25) with
67       a diameter of .1 .
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69       Use the ncargex command to see the following relevant example:
70       fngngdts.
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ACCESS

73       To use NGDOTS or c_ngdots, load the NCAR Graphics libraries ncarg,
74       ncarg_gks, and ncarg_c, preferably in that order.
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MESSAGES

77       Warning messages will be issued if one calls NGDOTS after having called
78       SET with any final argument other than "1".
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SEE ALSO

81       Online: gpm(3NCARG), point(3NCARG), points(3NCARG), set(3NCARG),
82       ncarg_cbind(3NCARG)
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84       Online URL: http://ngwww.ucar.edu/ngdoc/ng/gks/gkshome.html
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86       Hardcopy: NCAR Graphics Fundamentals, UNIX Version; "The Use of X/Y
87       Coordinates in NCAR Graphics" SCD User Document
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90       Copyright (C) 1987-2009
91       University Corporation for Atmospheric Research
92       The use of this Software is governed by a License Agreement.
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96UNIX                              March 1993                    NGDOTS(3NCARG)
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