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For x = 2.5, this relation returns

y=6.25

NOTE: In case you apply the symbolic addressing of the columns for the description of the point on the curve or surface to compute the differential for, e.g. "Par_x" and "Par_y", please make sure that your Telitab set contains these names. If not, an error message is generated and the calculation is stopped.

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If Pno%=0 then all x_i and y_i values should be numeric expressions. The minimum number of x,y data points Npoints% in the list is 2 in which case the interpolation (and differentiation) is performed linear. Let y be a function defined by

y = DIFF(0, 4, 1, 1, 2, 4, 3, 9, 4, 16, x, 1)

For x=2.5, this equation returns

y=6.25

Syntax 3 and 4: TeLiTab in object or string

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