Using Regrid2 to display wind barbs

[Tye Parzybok]

I'm trying to display wind barbs at a higher resolution than the native
resolution (2.5 x 2.5 degrees) of my GRIB data using regrid2. This is my
sequence of steps in GrADS:

open <filename>.ctl
set gxout barb
d regrid2(ugrdprs(t=1,lev=1000);vgrdprs(t=1,lev=1000),0.5,0.5,bl)

And I get this error message:

Syntax Error:  Unmatched parens
  Error ocurred at column 1
DISPLAY error:  Invalid expression
  Expression = regrid2(ugrdprs(t=1,lev=1000)

Any ideas on how I can make this work?

Thank you in advance for any help, advice or tips.

-Tye