[R] Passing colnames to graphics title

[Uwe Ligges]

Laura Quinn wrote:

> Obviously I have been trying to use the colnames() function!
> 
> However, when I try to subscript ie:
> 
> for(i in 1:20){
> main=paste("Site:",colnames(i),sep="")
> }

Example (which you should have provided):

  # Generate an example-matrix:
  X <- matrix(1:9, 3)
  colnames(X) <- letters[1:3]

  # now try to get histograms of columns using a loop:
  par(mfrow = c(3, 1))
  cnames <- colnames(X)
  for(i in 1:ncol(X)){
    hist(X[,i], main = paste("Site:", cnames[i], sep=""))
  }

Uwe Ligges


> this doesn't work! I thought that as.character(colnames(i)) or
> substitute(colnames(i)) might work, but to no avail...
> 
> Laura Quinn
> Institute of Atmospheric Science
> School of Earth and Environment
> University of Leeds
> Leeds
> LS2 9JT
> 
> tel: +44 113 343 1596
> fax: +44 113 343 6716
> mail: laura at env.leeds.ac.uk
> 
> On Wed, 16 Feb 2005, Uwe Ligges wrote:
> 
> 
>>Laura Quinn wrote:
>>
>>
>>>Hi,
>>>
>>>Just a quick query - if I'm creating a function to produce a number of
>>>histograms per page of output (one per column from a matrix), how can I
>>>pass the column name of the matrix into the title (or indeed to form part
>>>of the x-axis label)?
>>
>>
>>By extracting them using colnames()?
>>
>>Uwe Ligges
>>
>>
>>
>>
>>>TIA,
>>>Laura
>>>
>>>Laura Quinn
>>>Institute of Atmospheric Science
>>>School of Earth and Environment
>>>University of Leeds
>>>Leeds
>>>LS2 9JT
>>>
>>>tel: +44 113 343 1596
>>>fax: +44 113 343 6716
>>>mail: laura at env.leeds.ac.uk
>>>
>>>______________________________________________
>>>R-help at stat.math.ethz.ch mailing list
>>>https://stat.ethz.ch/mailman/listinfo/r-help
>>>PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html
>>
>>