[R] problems using the thin plate spline method

Mintewab Bezabih Mintewab.Bezabih at economics.gu.se
Mon Dec 5 11:28:26 CET 2011

Dear Sarah and R users, 

Sorry again for not being explicit enough. Here is my full problem

dat <- read.table("E:/thin plate/thin plate.csv", header=T, sep=",")
names(dat) <- c("x1", "x2", "y")
plot (dat)

#load the fields package (containing Tps) and fit a thin plate spline
tpsfit <- Tps(cbind(x1, x2), y, scale.type="unscaled")

What I meant when I said the graph works is when I do plot(dat) it does plot of all my three variables. If I do plot(x1,y), though, I get the 'object x1 not found' error message. 

Same when I do the next line tpsfit <- Tps(cbind(x1, x2), y, scale.type="unscaled"). I get the same error message. 

I tried your suggestion of checking str(x1) and I get the same error message (object x1 not found). 
I also typed ls() and I get "dat" after that command. 

I followed the r tutorial guide to read my data and I am following the r tutorial to guide me to apply the thin plate spline method. 


Från: Sarah Goslee [sarah.goslee at gmail.com]
Skickat: den 4 december 2011 15:21
Till: Mintewab Bezabih
Kopia: r-help at r-project.org
Ämne: Re: [R] problems using the thin plate spline method


On Sun, Dec 4, 2011 at 8:08 AM, Mintewab Bezabih
<Mintewab.Bezabih at economics.gu.se> wrote:
> Dear R users and Jeff,
> Sorry for not being quite explicit in my earlier message.

And you are still not explicit. We have no idea what you've done.

> My main problem is while my data seem to be read into R well (I manage to graph them and all), I cannot get the following line to work.
> tpsfit <- Tps(cbind(x1, x2), y, scale.type="unscaled")
> and I get the following error message
> Error in as.matrix(x) :
>  error in evaluating the argument 'x' in selecting a method for function 'as.matrix': Error: object 'x1' not found

I'd have to guess that there's no object x1. What does ls() tell you? str(x1)?

What do your data look like? You were already given instructions on how to
include sample data to construct a reproducible example. You said that
graphing your data worked; how did you do so?

The posting guide and the advice you were already given were both
offered for a reason. The querent needs to do the work of formulating
an understandable and answerable question.


> thanks for help
> minti
> ________________________________________
> Från: Jeff Newmiller [jdnewmil at dcn.davis.ca.us]
> Skickat: den 3 december 2011 17:45
> Till: Mintewab Bezabih; r-help at r-project.org
> Ämne: Re: [R] problems using the thin plate spline method
> I can tell that you are puzzled and confused. Unfortunately, I am not psychic, so I cannot tell what you did, and therefore cannot tell where you went astray.
> The solution is for you to read the posting guide mentioned at the bottom of every R-help message. Spend a little time to create a small bit of data like yours if your actual data is large (subset and dput are useful for this). Remember to include the output of sessionInfo, and so on. Many times you are likely to find the answer yourself by going through these steps, but they are essential for communication.
> Good luck.
> Sent from my phone. Please excuse my brevity.
> Mintewab Bezabih <Mintewab.Bezabih at economics.gu.se> wrote:
>>Dear R users,
>>I am a beginner in R trying to apply the thin plate spline method to my
>>climate data. I used the example in R to do so, and the lines seem to
>>run fine ( I am not getting errors) but I am not getting any output in
>>the form of graph or anything. I got a warning message saying that
>>'surface extends beyond box'.
>>Any help is much appreciated.

Sarah Goslee

More information about the R-help mailing list