Discussed here is the polymarker output primitive GPM and the
functions that are used to set polymarker attributes and retrieve
current attribute settings.
The polymarker output primitive GPM causes N markers to be drawn at
the locations specified by the coordinate pairs (X(I),Y(I)) for I=1,N.
The markers can be either a
dot, a plus sign, an asterisk (the default), a circle, or a cross.
-------------------------------------------------
Argument | Type | Mode | Dimension
-------------------------------------------------
CALL GPM (N, | Integer | Input |
X, | Real | Input | N
Y) | Real | Input | N
-------------------------------------------------
- N
- The number of markers to be drawn. (N > 0)
- X
- An array of dimension N containing the X coordinates of the
N markers to be drawn, in world coordinates.
- Y
- An array of dimension N. The Y coordinates of the
N markers to be drawn, in world coordinates.
- Defaults:
- none
- Errors:
- 5,
100
By default, the polymarker type is an asterisk.
To select other polymarker types and attributes, see
Setting Polymarker Attributes.
All standardized polymarkers are symmetric and
will be centered on the specified coordinates.
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C Synopsis
#include <ncarg/gks.h>
void gpolymarker(
const Gpoint_list *point_list /* list of points */
);
--------------------------------------------------------------------------
Figure 7
- Examples of polymarkers
You can set polymarker types and sizes using GSMK and GSMKSC, respectively.
-------------------------------------------------
Argument | Type | Mode | Dimension
-------------------------------------------------
CALL GSMK (MTYPE) | Integer | Input |
-------------------------------------------------
- MTYPE
- Selects the type of marker to be drawn. Options are:
- < 0 - implementation dependent (not used in NCAR GKS)
- 1 - . (dot)
- 2 - + (plus)
- 3 - * (asterisk)
- 4 - o (circle)
- 5 - X (cross)
- >= 6 - reserved for registration or future standardization
- Default:
- The default polymarker is an asterisk.
- Errors:
- 8,
69
--------------------------------------------------------------------
C Synopsis
#include <ncarg/gks.h>
void gset_marker_type(
Gint marker_type /* marker type */
);
--------------------------------------------------------------------
-------------------------------------------------
Argument | Type | Mode | Dimension
-------------------------------------------------
CALL GSMKSC (MSZSF) | Real | Input |
-------------------------------------------------
- MSZSF
- A scale factor to control the size of the marker. It must be
greater than or equal to 0.
- Default:
- 1.0
- Errors:
- 8
The GKS standard requires that marker type 1
always be displayed as
the smallest possible dot. For this reason a dot marker will not
be scaled, regardless of the value of MSZSF. To get filled dots
of any size and color, use the
NGDOTS utility.
--------------------------------------------------------------------------
C Synopsis
#include <ncarg/gks.h>
void gset_marker_size(
Gdouble marker_size /* marker size scale factor */
);
--------------------------------------------------------------------------
--------------------------------------------------
Argument | Type | Mode | Dimension
--------------------------------------------------
CALL GQMK (ERRIND, | Integer | Output |
MTYPE) | Integer | Output |
--------------------------------------------------
- ERRIND
- Error flag. Gives an integer error number from the errors list in
in Appendix D,
or a 0 if no error occurred.
- MTYPE
- The polymarker type as set by GSMK.
- Errors:
- 8
-------------------------------------------------------------------------
C Synopsis
#include <ncarg/gks.h>
void ginq_marker_type(
Gint *err_ind, /* error indicator */
Gint *marker_type /* current marker type */
);
-------------------------------------------------------------------------
----------------------------------------------------
Argument | Type | Mode | Dimension
----------------------------------------------------
CALL GQMKSC (ERRIND, | Integer | Output |
MSZSF) | Real | Output |
----------------------------------------------------
- ERRIND
- Error flag. Gives an integer error number from the errors list in
in Appendix D,
or a 0 if no error occurred.
- MSZSF
- Gives the marker size scale factor as set by GSMKSC.
- Errors:
- 8
----------------------------------------------------------------------------
C Synopsis
#include <ncarg/gks.h>
void ginq_marker_size(
Gint *err_ind, /* error indicator */
Gint *marker_size /* marker size scale factor */
);
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