The Excel curve is based on three control points, the Math::Interpolate one is based on five controls.

I presume that means the excel plot is using a quadratic interpolation (3 pts).

If that's true, then you need to set M:I to use a quadratic interpolation as well if you want the results to match closely. Even then, using a different set of data (5 pts instead of 3) will ensure that your interpolation is slightly different.

If you want it to be exact, you need to use the exact same input.

In reply to Re^3: 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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