Count the contigs length in index fasta file with samtools. $ awk '{s+=$2}END{print s}' scaffolds.fasta.fai #Fasta #Index #Length #Count #Size #Samtools
Extract a fasta sequence from multifasta file: samtools faidx multitest.fa and then samtools faidx multitest.fa fasta_id > out.fa #Samtools #Fasta #Extract #Multifasta