Re: constant values

[<Mick.Spillane@xxxxxxxx>]

On Fri, 25 Feb 2005, James Booth wrote:
> I write a surface tracer flux to a netcdf file.  If the flux is a constant
> value (non-zero) the fill and cont plots show nothing.

Hello Jimmy,
	There is nothing you can do with a line contour plot I'd say
except perhaps to customize your script to write a label like
"Constant Value=..." in the middle of the field.
	However, in the case of fill or shade, you can "fake it out"
by adding a tiny variation at the noise level of the variable you are
plotting.
	For example

fill/i=1:8/j=1:6/lev=(1,10,1) 0*(i+j)+5 ! a constant value of 5 produces a
                                        ! blank field and no key
! but try the following ...
fill/i=1:8/j=1:6/lev=(1,10,1) 0.00001*(i+j)+5

! So if you have a variable "v" to fill, and it has the potential to be
! constant then, if it is in on a grid "grd" in the x-y plane, you might
! try something like
!	let tol=0.00001
!	fill/lev=(1,10,1) (1+tol*(x[g=grd]+y[g=grd]))*v
! where tol is a small number near the limit of ferret's precision

Good luck,
Mick