# List-manipulation Interpolation

For example, I have the following list:

AA={{0, 20000.}, {26.6, 19950.}, {53.2, 19950.}, {79.8,
19950.}, {97.1198, 18644.1}, {102.681, 16452.3}}


Another calculation results in an arbitrary value intended for the first part of the list, let's say 21.3. By interpolating linearly, this results in a value of 19960 for the second part of the list.

How can I import this in Mathematica?

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what would an improvement look like? What value would you expect? –  user21 Jul 24 '13 at 17:57
I would expect an value of 19960 (In case of 21.3 in the first part of the list), but I don't know how to program this in Mathematica.. –  Paus Jul 24 '13 at 18:04

If you use an InteprolationOrder->1 things work as you expect:
if = Interpolation[AA, InterpolationOrder -> 1];