[R] connecting points into a smooth curve

[Gavin Simpson]

On Sun, 2010-10-31 at 23:18 -0700, tooblue wrote:
> If I have, say, five scatter points and want to connect them together into a
> smooth curve.
> I did plot(x,y,type="l"), but the graph is five segments connecting with
> each other, but not a smooth curve. 
> I wonder if there is a line type that is a curve. Thanks!

?spline would be one way of joining up the point with smooth curve
passing through the 5 observations. However, as several other have
noted, you need to explain how you want the smooth curve to pass through
the observations.

Here's an example:

x <- 1:5
y <- rnorm(5)
ylim <- with(sp, range(y))
plot(x,y, ylim = ylim)
lines(sp, col = "red")

HTH

G
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