interpolate | R Documentation |

Piece-wise cubic or linear spline interpolation.

```
interpolate (y, x = 1:length(y), steps = 20, increment = -1,
show = FALSE, type = 'cubic', ...)
```

`y` |
A vector of 'knots', between which the function will interpolate points. |

`x` |
The 'x' coordinates corresponding to each knot. If not specified, the knots are assumed to be equally spaced. |

`steps` |
The number of interpolating steps between each knot. Increasing this number will result in a smoother interpolation. If the knots are not equally spaced along the x-axis, the interpolated points will not be equally spaced across the entire curve. |

`increment` |
If this is greater than 0, interpolated points are separated along the x-axis by this value. Note that if the knot locations are not multiples of this increment, there will be irregularities in the spacing of the interpolated points. |

`show` |
If TRUE, the result of the interpolation is shown in a plot. |

`type` |
If 'cubic', a natural cubic spline interpolation is performed. If 'linear', a linear interpolation is performed. |

`...` |
Additional arguments are passed to the internal call of plot() if show = TRUE. |

By default, this function performs a 'natural' cubic spline interpolation between the points provided by the user. Optionally, a linear interpolation between the points may be carried out.

A dataframe with columns corresponding to the x and y dimensions of the interpolated points is returned.

`x` |
The x-axis coordinates of the interpolated points. |

`y` |
The y-axis coordinates of the interpolated points. |

Santiago Barreda <sbarreda@ucdavis.edu>

http://en.wikipedia.org/wiki/Spline_interpolation

```
## generate ten random points
#y = rnorm (10, 0, 5)
#interpolate (y, show = TRUE) ## plot a cubic interpolation
#linear = interpolate (y, type = 'linear')
## and compare to a linear interpolation
#lines (linear, col = 2)
```

Embedding an R snippet on your website

Add the following code to your website.

For more information on customizing the embed code, read Embedding Snippets.