vis/directgraphics/

mg_usersym.pro

direct graphics

includes main-level program

Creates a user-defined symbol for use in plotting in direct graphics via routines that accept the PSYM graphics keyword. All user symbols are scaled to fill the -1 to 1 range (use SYMSIZE of the graphics routine to change the size of the symbol).

Examples

Try the main-level example program at the end of this file:

  IDL> .run mg_usersym

The core lines of code to produce the plot are:

  plot, [0, 1], [0, 1], /nodata, xrange=[0, 1], yrange=[0, 1], $
        xstyle=9, ystyle=9
  oplot, randomu(seed, 10), randomu(seed, 10), $
         psym=mg_usersym(/circle, /fill, color=128B)
  oplot, randomu(seed, 10), randomu(seed, 10), $
         psym=mg_usersym(/triangle, rotation=90, /fill)
  oplot, randomu(seed, 10), randomu(seed, 10), $
         psym=mg_usersym(/triangle, rotation=-90, color=64B)
  oplot, randomu(seed, 10), randomu(seed, 10), $
         psym=mg_usersym(/hexagon)

It should look something like:

Routines

top mg_usersym

result = mg_usersym( [x] [, y] [, color=color] [, /fill] [, thick=float] [, /with_line] [, /none] [, /plus_sign] [, /asterisk] [, /dot] [, /diamond] [, /x] [, /user_defined] [, /histogram] [, /horizontal_line] [, /vertical_line] [, /triangle] [, /square] [, /hexagon] [, /circle] [, n_vertices=long] [, rotation=float])

Create a user symbol.

Return value

correct PSYM value for pre-defined types, 8 for the special symbols, i.e. PSYM=8 means use the current user symbol

Parameters

x in optional type=fltarr

x-values of the user symbol's shape

y in optional type=fltarr

y-values of the user symbol's shape

Keywords

color in optional type=color: color for the symbol
fill in optional type=boolean: set to fill inside the symbol
thick in optional type=float default=1.0: line thickness of the symbol
with_line in optional type=boolean: set to display symbols and a line connecting them; the default is to show just the symbol
none in optional type=boolean: set to produce no symbol
plus_sign in optional type=boolean: set to produce a plus sign symbol
asterisk in optional type=boolean: set to produce an asterisk symbol
dot in optional type=boolean: set to produce a dot symbol
diamond in optional type=boolean: set to produce a diamond symbol
x in optional type=boolean: set to produce an x symbol
user_defined in optional type=boolean: set to use the currently defined user symbol
histogram in optional type=boolean: set to use histogram mode
horizontal_line in optional type=boolean: set to produce a horizontal line user symbol
vertical_line in optional type=boolean: set to produce a vertical line user symbol
triangle in optional type=boolean: set to produce a triangular user symbol
square in optional type=boolean: set to produce a square
hexagon in optional type=boolean: set to produce a hexagonal user symbol
circle in optional type=boolean: set to produce a circular user symbol
n_vertices in optional type=long: number of vertices for a regular polygonal symbol
rotation in optional type=float default=0.0: angle in degrees to rotate the symbol; 0 degrees places the first vertex at (1, 0) in user symbol coordinate space

File attributes

Modification date:	Wed May 14 15:07:15 2014
Lines:	83
Docformat:	rst rst

Personal library of Michael Galloy
Contact me if you have enhancement requests or bug fixes.

mglib

Personal IDL library for M. Galloy