It would probably be a good idea to plot your results and then consider whether you are feeding the right data in and whether you've got that data in the right format, and whether you're using the right kind of interpolation for your task. The interpolation itself is almost certainly correct, and tweaking the values afterwards is never the right thing to do.

If the interpolation is quadratic or higher, then you will likely see some points in the interpolation that are higher than your maximum sample value.

Scaling the values down would make all the values (except zeroes) wrong in that case.

Consider this interpolation, where data points are the stars:
          __
       __/  \__
     _/        *_
   _*            \_
  /                \
 /                  \
*                    *

[download]

Many of the interpolated points are much higher than the highest sample. As they should be.

If your data is noisy, then the interpolation may not actually pass through any of the points. But that's also OK.

          *
 *     *      *     *
----------------------
     *       *     *
  *                *

[download]

In reply to Re: operate on an array created in a subroutine by SuicideJunkie
in thread operate on an array created in a while loop by captainentropy

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