Dear All, I am trying to analysis traffic data with one timestamp column and speed column. This data set contains six years data; for each year, I want to make a matrix in (day of the year) * (hour) 0 1 2 . . . 23 1 2 . . 365
However random day's record is missing(e.g. there are 40 missing records in 2005 data set), when I tried to use tapply function, matrix came out is 326*23 table and there were no N/A remind me which day is missing data. Can you give some hints to make a 366*24 table please? Any help is appreciated. Jessica -- View this message in context: http://r.789695.n4.nabble.com/How-to-make-matrix-missing-data-0-tp3652352p3652352.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.