About draw mark command

[Eric Altshuler]

You can use the query command to convert from geographic (world) coordinates to screen (virtual page) coordinates. First you need to display something, for example a variable 'var'.

d var
q w2xy LON LAT

where (LON,LAT) are the longitude and latitude of the point where you want to draw the mark. The output from the 'q w2xy' command will be of the form:

X = xpos  Y = ypos

where (xpos,ypos) are the virtual page coordinates of the point with geographic coordinates (LON,LAT). To draw the mark, do:

draw mark MARKTYPE xpos ypos SIZE

See http://grads.iges.org/grads/gadoc/gradcomddrawmark.html for documentation on the 'draw mark' command.

Best regards,

Eric L. Altshuler
Assistant Research Scientist
Center for Ocean-Land-Atmosphere Studies
4041 Powder Mill Road, Suite 302
Calverton, MD 20705-3106
USA

E-mail: ela at cola.iges.org
Phone: (301) 902-1257
Fax: (301) 595-9793

----- Original Message -----
From: "hersala" <hersala at GMAIL.COM>
To: GRADSUSR at LIST.CINECA.IT
Sent: Wednesday, June 10, 2009 2:34:57 PM GMT -05:00 US/Canada Eastern
Subject: About draw mark command

Hi Gradsusers,
Has anybody know how to use de *draw mark* command using geographic
coordinates instead of x and y inches (on the virtual page) as it is set as
default ?
Tks in advance !
Hernán