Re: [ferret_users] How to plot polygons?

[mick spillane <mick.spillane@xxxxxxxx>]

Hi Kek,
   For data laid out like that I think it would be better to read it in 
on a grid.  With four vertices per polygon and say 100 polygons you 
might then use:

   def axis/x=1:100:1 xax ;def axis/y=1:4:1 yax ; def grid/x=xax/y=yax grd
   file/g=grd/var=xx,yy/col=8/ord=yx testpoly.d
   poly/line=2/coord=y xx,yy

This will draw all the polygons with a red line perimeter.  The 
important step here is to get the reading order right - that is the 
purpose of the "var=xx,yy/col=8/ord=yx" in the "file" command which says 
to read all four pairs from a record arranged as x1,y1,x2,y2,x3,y3,x4,y4 
like in your situation.

Good luck,
Mick
-------
hengkek@xxxxxxxxxx wrote:
> Hi all
>
> I have an ascii file with 8 columns and multiple rows in the following 
> format:
>
> x1 y1 x2 y2 x3 y3 x4 y4
> ...
>
> where (x1,y1) thru (x4,y4) are vertices of polygons I'd like to plot.
>
> I'm not sure how to form the arrays to use POLYGON.  I.e. what to do 
> after "FILE/VAR=X1,Y1,X2,Y2,X3,Y3,X4,Y4 MYFILE.TXT"?
>
> Thanks for any tips.
>
> Sincerely
> Kek