Curve fitting with different number of points

This is probably a silly question. Is there a way to curve fit waves with different number of points besides creating a dummy wave to force them to match? E.g. if I have 7 y-data points, but 10 x-data points, do I have to make a dummy x-wave with only 7 points, or is there an easier solution? Thank you.
If you're willing to work on the command line, you can use wave subranges. Something like this:
CurveFit line, ydata /X=xdata[0,6]

There are almost certain to be other things required as part of this command line...
You can use the dialog to generate most of the command (like, select the Y wave but _calculated_ for the X wave), click To Cmd, and edit the command line to add the /X flag.

John Weeks
WaveMetrics, Inc.
support@wavemetrics.com