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Interpolate Extrapolate

Image:Video_Image.png See more related video:Origin VT-0010 Interpolation


Interpolation is a method of estimating and constructing new data points from a discrete set of known data points. This function generates uniform linear spaced interpolated curve by three methods: Linear, Cubic spline and Cubic B-spline.

To use this function:

  1. Create a new worksheet with input data.
  2. Select Analysis: Mathematics: Interpolate/Extrapolate. This opens interp1XY dialog.

In fact, the interpxy X-Function is called to complete the calculation.

Dialog Options


Specifies the XY range to be interpolated.


Specify the interpolation/extrapolation method.

  • Linear
    Linear interpolation is a fast method of estimating a data point by constructing a line between two neighboring data points. The resulting point may not be an accurate estimation of the missing dat.
  • Cubic Spline
    This method splits the input data into a given number of pieces, and fits each segment with a cubic polynomial. The second derivative of each cubic function is set equal to zero. With these boundary conditions met, an entire function can be constructed in a piece-wise manner.
  • Cubic B-Spline
    This method also splits the input data into pieces, each segment is fitted with discrete Bezier splines.
Number of Points

Specifies the number of interpolated points.

X Minimum

The minimum X value of interpolated curve.

X Maximum

The maximum X value of interpolated curve.

Apparent Interpolation

It is available only when the interpolation is performed on a graph. It specifies whether to use the apparent values for interpolation if the types of the axes scales have been changed to other types.


Specifies the output XY data range


Detail algorithms please refer to the help of Interpolate Extrapolate Y from X