[R] Applying function to lots of separate data sets

Laura Quinn laura at env.leeds.ac.uk
Mon Sep 6 03:13:10 CEST 2004


Aha, apologies...I have just answered my own question - thanks for showing
me the light with lists, lots of time saving ahead!!

Laura

Laura Quinn
Institute of Atmospheric Science
School of the 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 Sun, 5 Sep 2004, Duncan Murdoch wrote:

> On Mon, 6 Sep 2004 01:14:40 +0100 (BST), Laura Quinn
> <laura at env.leeds.ac.uk> wrote:
>
> >I have a total mental block and can't find my way around this seemingly
> >simple problem:
> >
> >I have created a function such that:
> >
> >my_answer_1=myfuntion(my_input_1)
> >
> >I am wanting to perform this calculation over a large number of datasets,
> >but am having real difficulty calling and assigning - i think the problem
> >les in the fact that I need to paste for call and assign.
> >
> >this is my best attempt so far..I can't seem to find a way around this...
> >
> >for(i in 1:50)
> >eval(parse(text=paste("my_answer_",i,
> >    "<-myfunction(text=paste("my_input_",i,sep=""))",sep="")))
> >
> >can someone please point out where i am going wrong?
>
> Using paste() to construct variable names is overdone.  It's much
> better to put all of your data into a list in one object, then just
> use lapply() to apply a function to each element of the list.
>
> For examples, see ?lapply.
>
> Duncan Murdoch
>




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