[R] apply function within different groups
Hi,
I have a very big data frame and I would like to apply a function to one of the
columns within different groups and obtain another dataframe
My data frame is like this:
group var1 var2 myvar
group1 1 a 100
group2 2 b 200
group2 34 c 300
group3 5 d 400
group3 6 e 500
group4 7 f 600
and I woud like to apply this function to column myvar:
mifunc = function(vec) {
vec=as.vector(vec)
for (i in 1:(length(vec)-1)){
vec[i]=vec[i+1]-1
}
return(vec)
}
by the groups in column group. I would like to obtain the same dataframe but
with f(myvar) instead of myvar.
How can I do this?
Thanks,
Estefania
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Re: [R] apply function within different groups
Thanks a lot!!! It works perkectly!
Just one thing, is there a way to preserve my original data frame so i don´t
need to join both tables? I could do it with rbind but my original data frame
is not in order, so
Thanks again!
From: arun smartpink...@yahoo.com
To: Estefanía Gómez Galimberti tef...@yahoo.com
Cc: R help r-help@r-project.org
Sent: Thursday, May 23, 2013 12:48 PM
Subject: Re: [R] apply function within different groups
Hi,
May be this helps:
dat1- read.table(text=
group var1 var2 myvar
group1 1 a 100
group2 2 b 200
group2 34 c 300
group3 5 d 400
group3 6 e 500
group4 7 f 600
,sep=,header=TRUE,stringsAsFactors=FALSE)
library(plyr)
ddply(dat1,.(group),summarize, f_myvar=mifunc(myvar))
# group f_myvar
#1 group1 NA
#2 group2 299
#3 group2 300
#4 group3 499
#5 group3 500
#6 group4 NA
A.K.
- Original Message -
From: Estefanía Gómez Galimberti tef...@yahoo.com
To: r help help r-help@r-project.org
Cc:
Sent: Thursday, May 23, 2013 11:30 AM
Subject: [R] apply function within different groups
Hi,
I have a very big data frame and I would like to apply a function to one of the
columns within different groups and obtain another dataframe
My data frame is like this:
group var1 var2 myvar
group1 1 a 100
group2 2 b 200
group2 34 c 300
group3 5 d 400
group3 6 e 500
group4 7 f 600
and I woud like to apply this function to column myvar:
mifunc = function(vec) {
vec=as.vector(vec)
for (i in 1:(length(vec)-1)){
vec[i]=vec[i+1]-1
}
return(vec)
}
by the groups in column group. I would like to obtain the same dataframe but
with f(myvar) instead of myvar.
How can I do this?
Thanks,
Estefania
[[alternative HTML version deleted]]
__
R-help@r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.
[[alternative HTML version deleted]]
__
R-help@r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.
Re: [R] remove from column a group of elements I have in another vector
Thank you Sarah!! My data frame is b and I have to remove from column anslogin every value from vector quit b= ht dispsplit anslogin month_ 1038 162 4627 1 475 1 4305 1 205 103 4136 1 296 1 4627 1 784 9 51274 1 451 75 4593 1 quit= 4079 4081 4095 4096 4119 4134 So, i should do b[!(b$ansologin%in%quit),], right? How does the %in% work??? Is it a normal in and the not comes with the ! ate the beggining? I have never used it, so thanks for teaching me this!. Thanks again, Estefania From: Sarah Goslee sarah.gos...@gmail.com To: Estefanía Gómez Galimberti tef...@yahoo.com Cc: r-help@r-project.org r-help@r-project.org Sent: Friday, December 21, 2012 4:56 PM Subject: Re: [R] remove from column a group of elements I have in another vector You can probably do it with not in in R too: for a data frame x where you want to remove rows where values in column A are not in the vector y: x[!(x$A %in% y), ] If you'd provided a reproducible example, I could give code that works in your particular circumstance. Sarah On Fri, Dec 21, 2012 at 12:43 PM, Estefanía Gómez Galimberti tef...@yahoo.com wrote: Hi, I have a data frame and I would need to remove from one of the columns a group of elements I have in another vector. How can I do that? I know how to do it with criteria but i would need to do it in a more automatic way In SQL I would use where not in Thank you, Estefania -- Sarah Goslee http://www.functionaldiversity.org [[alternative HTML version deleted]] __ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
[R] remove from column a group of elements I have in another vector
Hi, I have a data frame and I would need to remove from one of the columns a group of elements I have in another vector. How can I do that? I know how to do it with criteria but i would need to do it in a more automatic way In SQL I would use where not in Thank you, Estefania [[alternative HTML version deleted]] __ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
