Hi, I am learning edgeR. I don't have any prior knowledge about programing language. When I got some exercises in case study 1, according to the edgeR's user's guide, I got an error. > d <- readDGE(targets, skip=5, comment.char="!") Error in `colnames<-`(`*tmp*`, value = c("1", "2", "3", "4")) : length of 'dimnames' [2] not equal to array extent I searched around, but I haven't fixed it yet. Any responses would be greatly appreciated. Thank you! -- output of sessionInfo(): > targets <- read.delim("Targets.txt",stringsAsFactors=FALSE) > targets file group description 1 NC1.txt NC Normal colon 2 NC2.txt NC Normal colon 3 Tu98.txt Tu tumour 4 Tu102.txt Tu tumour > d <- readDGE(targets, skip=5, comment.char="!") Error in `colnames<-`(`*tmp*`, value = c("1", "2", "3", "4")) : length of 'dimnames' [2] not equal to array extent > summary(targets) file group description Length:4 Length:4 Length:4 Class :character Class :character Class :character Mode :character Mode :character Mode :character > names(targets) [1] "file" "group" "description" > str(targets) 'data.frame': 4 obs. of 3 variables: $ file : chr "NC1.txt" "NC2.txt" "Tu98.txt" "Tu102.txt" $ group : chr "NC" "NC" "Tu" "Tu" $ description: chr "Normal colon" "Normal colon" "tumour" "tumour" -- Sent via the guest posting facility at bioconductor.org.