Review
You've covered a lot of stringr functions in this chapter:
As a review we've got a few tasks for you to do with some DNA sequences. We've put three sequences, corresponding to three genes, from the genome of Yersinia pestis – the bacteria that causes bubonic plague – into the vector genes.
Each string represents a gene, each character a particular nucleotide: Adenine, Cytosine, Guanine or Thymine.
We aren't going to tell you which function to use. It's up to you to choose the right one and specify the needed arguments. Good luck!
Este exercício faz parte do curso
String Manipulation with stringr in R
Instruções do exercício
- Find the number of nucleotides in each gene.
- Find the number of
A's that occur in each gene. - Return the sequences that contain the sequence
"TTTTTT". - Replace all the
As in the sequences with a_.
Exercício interativo prático
Experimente este exercício completando este código de exemplo.
# Find the number of nucleotides in each sequence
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# Find the number of A's occur in each sequence
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# Return the sequences that contain "TTTTTT"
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# Replace all the "A"s in the sequences with a "_"
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