[R] legend title

[Cable, Samuel B Civ USAF AFMC AFRL/RVBXI]

Thanks to everyone who helped earlier today.

I am still working on multiple (4, exactly) contour plots of a data
frame "nd.frame" with contourplot():

contourplot(zdf~xdf*ydf|factor(pndf),data=nd.frame)

Everything is looking nice now, except I need to add a title to the
color bar, or "key".  It seems to me that this must be fairly
elementary, but I have looked through three books and Google, and can't
figure out how to do it.  I have tried several things that produce
either errors or nothing at all.

Can anyone tell me how to add a title to the color bar of a set of
contour plots?

Thanks again!

--Sam Cable