Hello R list subscribers, I am trying to use the "by" command to create line-specific variance covariance matrices (where "x" is the original data matrix):
by(x, x$line, function(d) { d.clean <- d[,-1]}) write.table(d.clean$line[1,1], sep = ",", file = "covariances.csv", col.names = FALSE, row.names = FALSE, append = TRUE) write.table("", sep = ",", file = "covariances.csv", col.names = FALSE, row.names = FALSE, append = TRUE) x.cov <- cov(d.clean, y= NULL, use= "complete.obs", method= c("pearson")) }) When I run this code, I get an error: > by(x, x$line, function(d) { + d.clean <- d[,-1]}) Error in names(IND) <- deparse(substitute(INDICES))[1] : 'names' attribute [1] must be the same length as the vector [0] Any suggestions on how to improve my code? Thanks in advance. Sincerely, Josh [[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.