# coyote: CGARROW

- coyote/Graphics
- [Source code]

Description

      Provides a device-independent and color-model-independent way of drawing an arrow
      in a specified color.
      The program requires the `Coyote Library <http://www.idlcoyote.com/documents/programs.php>`
      to be installed on your machine.

Categories

      Graphics

Params

      x0: in, required, type=integer/float
           The x location of the blunt end of the arrow. May be a vector. Assumes
           device coordinates.
      y0: in, required, type=integer/float
           The y location of the blunt end of the arrow. May be a vector. Assumes
           device coordinates.
      x1: in, required, type=integer/float
           The x location of the sharp end of the arrow. May be a vector. Assumes
           device coordinates.
      y1: in, required, type=integer/float
           The y location of the sharp end of the arrow. May be a vector. Assumes
           device coordinates.

Keywords

      addcmd: in, optional, type=boolean, default=0
          An alternative way to set the `Window` keyword.
      clip: in, optional, type=boolean, default=0
          Set the keyword to clip arrow output to the clipping rectangle specified
          in the `CRect` keyword. See the documentation for the IDL graphics
          keyword NOCLIP.
      color: in, optional, type=string/integer/long, default='white'
          An alternative way to specify the color to use in erasing the graphics window.
          Color names are those used with cgColor. This parameter is used in
          preference to the background_color parameter.
      crect: in, optional, type=float
           A four-element array giving the clipping rectangle [xo, yo, x1, y1]. The
           default clipping rectangle is the plot area. See the documenation for the
           IDL graphics keyword CLIP.
      data: in, optional, type=boolean, default=0
           Set this keyword of the arrow locations are in data coordinates.
           Device coordinates are assumed.
      hsize: in, optional, type=float
          The size of the the arrow head. By default 1/64th the width
          of the device. (!D.X_SIZE / 64.)
      hthick: in, optional, type=float, default=1.0
          The thickness of the line drawing the arrowhead.
      linestyle: in, optional, type=integer, default=0
          The line style of the arrow. Line style integers as in PLOT.
      normal: in, optional, type=boolean, default=0
           Set this keyword of the arrow locations are in normalized coordinates.
           Device coordinates are assumed.
      solid: in, optional, type=boolean, default=0
           Set this keyword to draw solid, filled arrows.
      thick: in, optional, type=float, default=1.0
          The thickness of the line drawing the shaft of the arrow.
      window: in, optional, type=boolean, default=0
          Set this keyword to add the command to an cgWindow application.

Examples

      Used to draw arrows::
         IDL> cgArrow, 50, 50, 100, 100, /Solid

Author

      FANNING SOFTWARE CONSULTING::
          David W. Fanning
          1645 Sheely Drive
          Fort Collins, CO 80526 USA
          Phone: 970-221-0438
          E-mail: david@idlcoyote.com
          Coyote's Guide to IDL Programming: http://www.idlcoyote.com

History

      Change History::
         Written, 23 November 2010. DWF. Based on old Arrow routine in IDL.
         Added Window keyword 24 January 2011. DWF.
         Modified error handler to restore the entry decomposition state if there is an error. 17 March 2011. DWF
         Added the ADDCMD keyword to make the interface more consistent with other Coyote Grapics routines. 18 April 2013. DWF.
         Modified to allow a vector of colors to be added with the COLOR keyword. 23 February 2015. DWF.
         Algorithm modified slightly to get the program a little closer to the machine to speed up
            vector drawing when there are lots of vectors. 23 February 2015. DWF.

Copyright

      Copyright (c) 2010-2015, Fanning Software Consulting, Inc.