I am trying to set up a function which processes my data according to the following rules:
1. if (x[i]==0) NA 2. if (x[i]>0) log(x[i]/(number of consecutive zeros immediately preceding it +1)) The data this will apply to include a variety of whole numbers not limited to 1 & 0, a number of which may appear consecutively and not separated by zeros. Below is an example with a detailed explanation of the output desired: x <- c(3,2,0,1,0,2,0,0,1,0,0,0,0,4,1) output desired = c(1.098, 0.69, NA, -0.69, NA, -0.41, NA, NA, 1.098, NA, NA, NA, NA, -0.22, 0) the 1st element, 3, becomes log(3) = 1.098612 the 2nd element, 2, becomes log(2) = 0.6931472 the 3rd element, 0, becomes NA (cannot log zero). the 4rd element, 1, becomes log(1/(1(number of consecutive zeros immediately preceding it) + 1 (constant))) = log(1/2) = -0.6931472 the 5th element, 0, becomes NA the 6th element, 2, becomes log(2/(1(number of consecutive zeros immediately preceding it) + 1 (constant))) = log(2/3) = -0.4054651 the 7th and 8th elements, both zeros, become NA the 9th element, 1, becomes log(1/(2(number of consecutive zeros immediately preceding it) + 1 (constant))) = log(1/3) = 1.098612 the 10-13th elements, all zeros, each become NA the 14th element, 4, becomes log(4/(4(number of consecutive zeros immediately preceding it) + 1 (constant))) = log(4/5) = -0.2231436 the 15th element, 1, becomes log(1) = 0 This one has been in the works for some time and I can't quite seem to crack it. I would be indebted to anyone who could with success - it seemed so simple at the offset! Tyler -- View this message in context: http://www.nabble.com/NOT-SO-SIMPLE-function%21-tp17607348p17607348.html Sent from the R help mailing list archive at Nabble.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.
