Re: Vectors and module in an alternative way

[Ansley Manke <manke@xxxxxxxxxxx>]

Hi Salvador,
Ferret could do this in only a very rudimentary way, using the VECTOR/COLOR
option and a mask, along these lines: If the velocity is in a variable 
called vel,
and the component vectors are u, v:

  let velmask = if vel le 10 then 1
  let umask = u * velmask
  let vmask = v * velmask
  plot/color=red umask, vmask

  let  velmask = if vel gt 10 and vel lt 15 then 1
  plot/over/color=blue umask, vmask

  etc.

This is limited by the very few colors available for the COLOR=
qualifier.  
The polygon command has the ability to color the polygons
according to the value of a variable, but the way VECTOR is
implemented does not allow this.  Could one use the POLYGON
command to do such a plot?  Anyone want to think about that?

Ansley  
Salvador Calabria Montero wrote:

> Hello everybody:
>
> I have got a NetCDF set of wind data and I'd like to get a draw like this:
> The field of velocity modules and the field of vectors in this way: vectors 
> coloured follwing the velocity module and a set of levels defined. In other 
> words, instead of having a velocity field and a vector field overlaying it, i 
> wonder if it is possible to get such configuration from Ferret. 
> Thank in advance for your help