[R] Filling in a series
Colleagues After reading in some clinical data, I discovered that the subject ID column contains entries only for the first record for each individual; subsequent rows are recorded as NA. For example: 1 NA NA NA NA 2 NA NA NA NA 3 NA NA ... I can think of various approaches to replace the NA values with appropriate entries. I could loop through each row - if the value is NA, I replace it with the entry from the row above. Or, I could find the positions of the non-NA values with match, then replace groups of entries (e.g., positions 2-5) with appropriate entries, again with a loop. But, I expect that R allows some more clever approach to the problem. Any thoughts? Dennis Dennis Fisher MD P (The P Less Than Company) Phone: 1-866-PLessThan (1-866-753-7784) Fax: 1-415-564-2220 www.PLessThan.com [[alternative HTML version deleted]] __ R-help@stat.math.ethz.ch 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] Filling in a series
The zoo package has na.locf (last occurrernce carried foward) for this purpose: x [1] 1 NA NA NA NA 2 NA NA NA NA 3 NA NA library(zoo) na.locf(x) [1] 1 1 1 1 1 2 2 2 2 2 3 3 3 On 10/21/06, Dennis Fisher [EMAIL PROTECTED] wrote: Colleagues After reading in some clinical data, I discovered that the subject ID column contains entries only for the first record for each individual; subsequent rows are recorded as NA. For example: 1 NA NA NA NA 2 NA NA NA NA 3 NA NA ... I can think of various approaches to replace the NA values with appropriate entries. I could loop through each row - if the value is NA, I replace it with the entry from the row above. Or, I could find the positions of the non-NA values with match, then replace groups of entries (e.g., positions 2-5) with appropriate entries, again with a loop. But, I expect that R allows some more clever approach to the problem. Any thoughts? Dennis Dennis Fisher MD P (The P Less Than Company) Phone: 1-866-PLessThan (1-866-753-7784) Fax: 1-415-564-2220 www.PLessThan.com [[alternative HTML version deleted]] __ R-help@stat.math.ethz.ch 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@stat.math.ethz.ch 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] Filling in a series
Actually I think its last _observation_ carried forward. On 10/21/06, Gabor Grothendieck [EMAIL PROTECTED] wrote: The zoo package has na.locf (last occurrernce carried foward) for this purpose: x [1] 1 NA NA NA NA 2 NA NA NA NA 3 NA NA library(zoo) na.locf(x) [1] 1 1 1 1 1 2 2 2 2 2 3 3 3 On 10/21/06, Dennis Fisher [EMAIL PROTECTED] wrote: Colleagues After reading in some clinical data, I discovered that the subject ID column contains entries only for the first record for each individual; subsequent rows are recorded as NA. For example: 1 NA NA NA NA 2 NA NA NA NA 3 NA NA ... I can think of various approaches to replace the NA values with appropriate entries. I could loop through each row - if the value is NA, I replace it with the entry from the row above. Or, I could find the positions of the non-NA values with match, then replace groups of entries (e.g., positions 2-5) with appropriate entries, again with a loop. But, I expect that R allows some more clever approach to the problem. Any thoughts? Dennis Dennis Fisher MD P (The P Less Than Company) Phone: 1-866-PLessThan (1-866-753-7784) Fax: 1-415-564-2220 www.PLessThan.com [[alternative HTML version deleted]] __ R-help@stat.math.ethz.ch 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@stat.math.ethz.ch 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.
