Re-naming some sequences header within the fasta file

Question

[seta]

Dear all,

I got a large fasta file with two types of header, the header name for some sequences is contig and for some of them is cx_gx_ix. I want to rename all headers named contig to another name say c_g_i. Please help me how I should do it?

[Pierre Lindenbaum]

man sed http://linux.die.net/man/1/sed, http://unix.stackexchange.com/questions/112023

[seta]

Thanks friend

[Prakki Rama]

sed 's/>.*/>c_g_i/g' filename.fasta

[cvu]

Try this

sed -i 's/^>contig/>c_g_i/g' file.fasta