[R] Help Please!!!!!!!!!

[Paul]

On 29/11/10 05:29, Melissa Waldman wrote:
> Hi,
>
> I have been working with Program R for my stats class and I keep coming upon
> the same error, I have read so many sites about inputting data from a text
> file into R and I'm using the data to do a correspondence analysis.  I feel
> like I have read everything and it is still not explaining why the error
> message keeps coming up, I have used the exact examples I have seen in
> articles and the same error keeps popping up: Error in sum(N) : invalid
> 'type' (character) of argument
>
> I have spent sooooooooooooo long trying to figure this out without success,
> I am sure it has to do with the fact that my rows have names in them.  I
> have attached the text file I have been using and if you have any ideas as
> to how I can get R to plot the data using correspondence analysis with the
> column and row names that would be really helpful!  Or if you could pass
> this email to someone who may know how to help me, that would be much
> appreciated.
>
> Thank you,
> Melissa Waldman
>
>    
Hi Melissa,

Welcome to the world of R.  You didn't tell us which commands you were 
running that gave an error, but the error 'invalid 'type'' suggests to 
me you were trying to sum a variable that R thought was a character, and 
not a number.

I would recomend you (re) read the introduction to R 
(http://cran.r-project.org/doc/manuals/R-intro.pdf), especially chapter 
2, which deals with this.

As a quick example, if you've read your file into a dataframe called 
foo, with columns none, light etc then doing

class(foo$none)

will tell you what R thinks this field is.  If it is character then you 
can do

foo$none <- as.numeric(foo$none)

to tell R to treat it as numbers.

Regards,

Paul.