In R, how do I sub specific character from my data?

I have this :

20220801_NM7_Chrom_2399_A12_CCIH.CSV

I want get below

20220801_NM7_Chrom_2399_CCIH

Thanks for sparing your time.

>Solution :

• You can try this

x <- "20220801_NM7_Chrom_2399_A12_CCIH.CSV"

sub( "_A\\d+_" , "_", sub("\\..*" , "" , x))

• Output

"20220801_NM7_Chrom_2399_CCIH"