# Creating objects to work on:
sq_dna <- sq(c("ATGCAGGA", "GACCGNBAACGAN", "TGACGAGCTTA"),
alphabet = "dna_bsc")
sq_ami <- sq(c("MIAANYTWIL","TIAALGNIIYRAIE", "NYERTGHLI", "MAYXXXIALN"),
alphabet = "ami_ext")
sq_unt <- sq(c("ATGCAGGA?", "TGACGAGCTTA", "", "TIAALGNIIYRAIE"))
# Counting how may "A" elements are present in sequences:
sqapply(sq_dna, function(sequence) sum(sequence == "A"))
sqapply(sq_ami, function(sequence) sum(sequence == "A"))
sqapply(sq_unt, function(sequence) sum(sequence == "A"))
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