Re: [R] data frame row statistics (mean)?
Hello Doug,
I just wanted to add that a faster way to initialize a vector is:
avg <- vector("numeric", nrow(d))
Also you might like nrow(d) over length(d[ , 1]) if the number of rows
is what you are after. Its sister function is ncol() .
Best regards,
Josh
On Mon, Jun 28, 2010 at 11:37 AM, Douglas M. Hultstrand
wrote:
> Hello,
>
> I am trying to calculate the mean value of each row in a data frame (d), I
> am having troubles and getting errors using the code I have written. Below
> is a brief example of the code, any thought or suggestions would be great.
>
> Thank you for your time,
> Doug
>
>
> # Example Code:
> d <- data.frame(st1=c(1,2,3,4), st2=c(2,5,6,7), st3=c(5,5,NA,7),
> st4=c(6,5,7,8))
> avg <- rep(NA,length(d[,1]))
>
> for (i in 1:length(d[,1])) {
> avg[i] = mean(d[i,1:4], na.rm=TRUE)
> }
>
> # Final Output wanted.
> st1 st2 st3 st4 avg
> 1 1 2 5 6 3.50
> 2 2 5 5 5 4.25
> 3 3 6 NA 7 5.33
> 4 4 7 7 8 6.50
>
> --
> -
> Douglas M. Hultstrand, MS
> Senior Hydrometeorologist
> Metstat, Inc. Windsor, Colorado
> voice: 720.771.5840
> email: dmhul...@metstat.com
> web: http://www.metstat.com
>
> __
> 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.
>
--
Joshua Wiley
Ph.D. Student, Health Psychology
University of California, Los Angeles
http://www.joshuawiley.com/
__
R-help@r-project.org mailing list
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PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.
Re: [R] data frame row statistics (mean)?
Douglas M. Hultstrand wrote:
Hello,
I am trying to calculate the mean value of each row in a data frame (d),
I am having troubles and getting errors using the code I have written.
Below is a brief example of the code, any thought or suggestions would
be great.
Thank you for your time,
Doug
# Example Code:
d <- data.frame(st1=c(1,2,3,4), st2=c(2,5,6,7), st3=c(5,5,NA,7),
st4=c(6,5,7,8))
avg <- rep(NA,length(d[,1]))
for (i in 1:length(d[,1])) {
avg[i] = mean(d[i,1:4], na.rm=TRUE)
}
# Final Output wanted.
st1 st2 st3 st4 avg
1 1 2 5 6 3.50
2 2 5 5 5 4.25
3 3 6 NA 7 5.33
4 4 7 7 8 6.50
d$avg <- rowMeans(d, na.rm = TRUE)
__
R-help@r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.
Re: [R] data frame row statistics (mean)?
Doug -
Try
d$avg = apply(d,1,mean,na.rm=TRUE)
d
st1 st2 st3 st4 avg
1 1 2 5 6 3.50
2 2 5 5 5 4.25
3 3 6 NA 7 5.33
4 4 7 7 8 6.50
(If you must use a loop, calculate
mean(as.numeric(d[i,1:4]))
Take a look at mean(d[1,1:4]) to see why your
program doesn't work properly.)
- Phil Spector
Statistical Computing Facility
Department of Statistics
UC Berkeley
spec...@stat.berkeley.edu
On Mon, 28 Jun 2010, Douglas M. Hultstrand wrote:
Hello,
I am trying to calculate the mean value of each row in a data frame (d), I am
having troubles and getting errors using the code I have written. Below is a
brief example of the code, any thought or suggestions would be great.
Thank you for your time,
Doug
# Example Code:
d <- data.frame(st1=c(1,2,3,4), st2=c(2,5,6,7), st3=c(5,5,NA,7),
st4=c(6,5,7,8))
avg <- rep(NA,length(d[,1]))
for (i in 1:length(d[,1])) {
avg[i] = mean(d[i,1:4], na.rm=TRUE)
}
# Final Output wanted.
st1 st2 st3 st4 avg
1 1 2 5 6 3.50
2 2 5 5 5 4.25
3 3 6 NA 7 5.33
4 4 7 7 8 6.50
--
-
Douglas M. Hultstrand, MS
Senior Hydrometeorologist
Metstat, Inc. Windsor, Colorado
voice: 720.771.5840
email: dmhul...@metstat.com
web: http://www.metstat.com
__
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-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] data frame row statistics (mean)?
Hello,
I am trying to calculate the mean value of each row in a data frame (d),
I am having troubles and getting errors using the code I have written.
Below is a brief example of the code, any thought or suggestions would
be great.
Thank you for your time,
Doug
# Example Code:
d <- data.frame(st1=c(1,2,3,4), st2=c(2,5,6,7), st3=c(5,5,NA,7),
st4=c(6,5,7,8))
avg <- rep(NA,length(d[,1]))
for (i in 1:length(d[,1])) {
avg[i] = mean(d[i,1:4], na.rm=TRUE)
}
# Final Output wanted.
st1 st2 st3 st4 avg
1 1 2 5 6 3.50
2 2 5 5 5 4.25
3 3 6 NA 7 5.33
4 4 7 7 8 6.50
--
-
Douglas M. Hultstrand, MS
Senior Hydrometeorologist
Metstat, Inc. Windsor, Colorado
voice: 720.771.5840
email: dmhul...@metstat.com
web: http://www.metstat.com
__
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.
