Interpolate ( x1 ; y1 ; x2 ; y2 ; x )
Linear interpolation or extrapolation from two coordinate points
Average rating: 4.0 (39 votes) Log in to vote
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
Note: these functions are not guaranteed or supported by BrianDunning.com. Please contact the individual developer with any questions or problems.