I have a big data frame dim(df)= 29 20664. It contains mutation and copy number variation data for genes. The column names are actually gene names. The column names currently are gene1, gene2 .... gene20664.

How can I change the column names from 1 to 19862 as gene1_mut, gene2_mut ... gene19862_mut

and from 19863 to 20664 as gene19863_CNV, gene19864_CNV..... gene20664_CNV.

I was trying following

names(geneMC)[19863:20664]<-paste("cnv_",19863:ncol(geneMC),sep="")
names(geneMC)[19863:20664]<-sprintf("cnv_%d",19863:ncol(geneMC),sep="")
 

names<-colnames(df)

names.mut<-names[1:19862]

names.cnv<-names[19863:20664]

names.mut2<-paste(names.mut,"mut",sep="_")

names.cnv2<-paste(names.cnv,"cnv",sep="_")

new.names<-c(names.mut2,names.cnv2)

colnames(df)<-new.names