[R] Interpolation

[Remigijus Lapinskas]

Many thanks to all who replied to my e-mail. My problem was that I
had not known about the approx function.

By the way, if I have  x <- c(1990,1994,1995,1997), is there an
automated way to fill in the gaps, i.e., to get
c(1991,1992,1993,1996)?

Cheers,
Remigijus


Wednesday, February 12, 2003, 12:09:33 PM, you wrote:

PDB> Remigijus Lapinskas <remigijus.lapinskas at maf.vu.lt> writes:

>> Dear all,
>>
>> I have two vectors and connect the points by line segments:
>>
>> x <- c(1990,1994,1995,1997)
>> y <- c(30,40,80,20)
>> plot(x,y,type="l")
>>
>> I want to get the values of y's on these lines at missing x's,
>> i.e., at 1991,1992,1993,and 1996. Is there a simple way to do this?


PDB> approx(x,y,c(1991,1992,1993,1996))
PDB> plot(x,y,type="l")
PDB> points(approx(x,y,c(1991,1992,1993,1996)),pch="*",col="red",cex=5)

PDB> --
PDB>    O__  ---- Peter Dalgaard             Blegdamsvej 3
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