If I have data, like this:
A B C 1 GM1 100 2 DOX 10 3 GM2 3 4 GM3 99 5 MY 62 6 GMPN 30
How can I use R to make the data look like this: (select only "GM" data)
A B C 1 GM1 100 3 GM2 3 4 GM3 99
you can use grep
grep
df1[grep('GM\\d+', df1$B),] # A B C #1 1 GM1 100 #3 3 GM2 3 #4 4 GM3 99
Or as @ColonelBeauvel mentioned
subset(df1, grepl('GM\\d+', B))