Brian Dunning's FileMaker Custom Functions

Interpolate ( x1 ; y1 ; x2 ; y2 ; x )

Linear interpolation or extrapolation from two coordinate points

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Bill Holt   Bill Holt

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  Sample input:
Interpolate(13 ; 23 ; -6 ; 5 ; 16)
  Sample output:

  Function definition: (Copy & paste into FileMaker's Edit Custom Function window)

Given any two xy coordinates, this function will interpolate or extrapolate, linearly, to return the value of y for any known value of x. If the pair of points define a vertical line, or the first point is duplicated, or if one or more of the required entries are missing, the function returns the word "error".

rev: description and notation clarifications



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Note: these functions are not guaranteed or supported by Please contact the individual developer with any questions or problems.

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