How do you generate only the luma or chroma, etc?

[cipher]

Like, is there a script that can be loaded in vdmod to show a frame of only its Y channel, or U or V channel, or two of them but not all of 'em at once?
Thx!:)

[sh0dan]

stackvertical(greyscale().subtitle("Y"),stackhorizontal(utoy().subtitle("U"), vtoy().subtitle("V")))

Or written out:
y = greyscale().subtitle("Y")
u = utoy().subtitle("U")
v = vtoy().subtitle("V")

uv = stackhorizontal(u,v )
stackvertical(y,uv)