Linear interpolation creates a piecewise continuous function by connecting a set of data points with straight lines. This is useful for interpolating between the data points or for generating a set of equally spaced data points. Equally spaced data points are sometimes needed for numerical integration or digital filtering.

The form on this page accepts data points as two columns which can be input in the lower left text box. When the "Plot linear interpolation" button is pushed, the data points are plotted in red and the straight lines connecting them are plotted in blue. Points along the blue line equally spaced in $x$ appear in the text box at the lower right.

$f(x)$ | |

$x$ |