[R] Odp: Define column names to a series of data.frames

[Petr PIKAL]

Hi

This seems to be nice example why lists shall be used and not several data 
frames scattered in environment.

put your data frames to list
lapply(list.of.data, function(x) names(x) <- column_names)

Regards
Petr



r-help-bounces at r-project.org napsal dne 11.03.2010 13:33:33:

> Greets to the list!
> 
> I am aware that this topic has been discussed several times. And I've
> read quite some related posts [1]. Yet, can't seem to give a solution to
> my problem.
> 
> I have 6 data frames consisting of 6 rows x 7 columns put together from
> other data.frames.
> 
> Something like:
> 
>    a b c d e f g
> v1 # # # # # # # 
> v2 # # # # # # #
> v3 # # # # # # #
> v4 # # # # # # #
> v5 # # # # # # #
> v6 # # # # # # #
> 
> 
> I want to give the following column names to each data.frame: ("SDev",
> "PC1", "PC2", "PC3", "PC4", "PC5", "PC6")
> 
> Works fine for one data.frame:
> column_names <- c("SDev", "PC1", "PC2", "PC3", "PC4", "PC5", "PC6")
> names( df1 ) <- column_names
> 
> How is it to be done at once for all data.frames that the function
> objects(pattern = "SomePattern") can find?
> 
> I've tried several things with assign, get, paste, for but I am not
> getting anywhere. I need to integrate this in a function that can handle
> lot's of data.frames and not only 6.
> 
> Thank you, Nikos
> 
> 
> ---
> [1] I am stuck on this post:
> <http://www.mail-archive.com/r-help@stat.math.ethz.ch/msg32063.html>. 
> 
> It reads:
> 
> dframes <- c("a","b","c")
> cols <- c("one","two")
> df <- data.frame(11:20, 21:30)
> names(df) <- cols
> assign(dframes[2], df)
> 
> Can't understand the logic behind the "[2]".
> 
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