In general, a spline is a curve that connects two or more specific points, or that is defined by two or more points. The equation that defines a spline curve is made up of one or more polynomial curve sections. Depending on the complexity of your data, the function can be simple, or very complex.

Example plots from our Graph Gallery
[click on an image to see original graph]

Spline Curve Graph

Spline Curve Graph Example

With Origin's Spline graph, the ability to connect your data via a cubic spline function is automatic.

A spline curve connection can also be enabled on almost any line or line + symbol plot. Once enabled, Origin internally transforms your data set based on the calculated spline function. It then plots the result on your graph. Your original data set is not affected, and although the spline data set is held internally, it is possible to access it.

All the basic features of a line + symbol graph can be edited with this graph type. However, the line connection type should ideally be kept as it is since it is essentially what defines the line series graph.

To learn more about the finer details of line + symbol graph types, click on a link below:
Line details...*
Scatter details...*
Line and Symbol details...*