Hello,
I am trying to calculate the median of numbers across each row for the data
shown below , with the condition that if the number is negative, that it
should be ignored and the median should be taken of only the positive
numbers.
For eg: data is in Column A,B,C. Column D and E demonstrates what I want to
get as answer
A
B
C
Median
median value
-13.6688115
-32.50914055
-50.54011892
all negative, so ignore
NA
NA
-53.65656268
42.58599666
median C
42.58599666
33.30683089
18.93765489
-25.17024229
median A,B
26.12224289
The R script I have written is below( which doesnot do the job properly)
median.value<- matrix(nrow=nrow(data),ncol=1)
for(k in 1:nrow(data)){
median.value[k]<-median(data[which(data[k,]>0)])}
Can someone suggest me the correct R script to do what I have explained
above.
Thanks
Manisha
[[alternative HTML version deleted]]
Hi Manisha, Manisha Brahmachary wrote:> Hello, > > > > I am trying to calculate the median of numbers across each row for the data > shown below , with the condition that if the number is negative, that it > should be ignored and the median should be taken of only the positive > numbers. > > > > For eg: data is in Column A,B,C. Column D and E demonstrates what I want to > get as answer > > > > A > > B > > C > > Median > > median value > > -13.6688115 > > -32.50914055 > > -50.54011892 > > all negative, so ignore > > NA > > NA > > -53.65656268 > > 42.58599666 > > median C > > 42.58599666 > > 33.30683089 > > 18.93765489 > > -25.17024229 > > median A,B > > 26.12224289 > > > > The R script I have written is below( which doesnot do the job properly) > > > > median.value<- matrix(nrow=nrow(data),ncol=1) > > for(k in 1:nrow(data)){ > > median.value[k]<-median(data[which(data[k,]>0)])}meds <- apply(data, 1, function(x) ifelse(median(x) < 0, median(x[x >= 0]), median(x))) I would normally avoid variable names like data, as you are masking a function by the same name. Best, Jim> > > > Can someone suggest me the correct R script to do what I have explained > above. > > > > Thanks > > Manisha > > > > > [[alternative HTML version deleted]] > > ______________________________________________ > R-help at 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.-- James W. MacDonald, M.S. Biostatistician Douglas Lab University of Michigan Department of Human Genetics 5912 Buhl 1241 E. Catherine St. Ann Arbor MI 48109-5618 734-615-7826
On 7/20/2009 2:59 PM, Manisha Brahmachary wrote:> Hello, > > > > I am trying to calculate the median of numbers across each row for the data > shown below , with the condition that if the number is negative, that it > should be ignored and the median should be taken of only the positive > numbers. > > > > For eg: data is in Column A,B,C. Column D and E demonstrates what I want to > get as answer > > > > A > > B > > C > > Median > > median value > > -13.6688115 > > -32.50914055 > > -50.54011892 > > all negative, so ignore > > NA > > NA > > -53.65656268 > > 42.58599666 > > median C > > 42.58599666 > > 33.30683089 > > 18.93765489 > > -25.17024229 > > median A,B > > 26.12224289 > > > > The R script I have written is below( which doesnot do the job properly) > > > > median.value<- matrix(nrow=nrow(data),ncol=1) > > for(k in 1:nrow(data)){ > > median.value[k]<-median(data[which(data[k,]>0)])} > > > > Can someone suggest me the correct R script to do what I have explained > above.X <- as.data.frame(matrix(rnorm(100), ncol=10)) apply(X, 1, function(x){median(x[x > 0])}) [1] 0.2297943 0.6476565 0.4699609 0.8744830 [5] 1.0242502 0.7800703 0.6648436 0.2930191 [9] 0.6001506 1.0767194> Thanks > > Manisha > > [[alternative HTML version deleted]] > > ______________________________________________ > R-help at 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.-- Chuck Cleland, Ph.D. NDRI, Inc. (www.ndri.org) 71 West 23rd Street, 8th floor New York, NY 10010 tel: (212) 845-4495 (Tu, Th) tel: (732) 512-0171 (M, W, F) fax: (917) 438-0894