Select n sequences from a collection

Let’s load an alignment of primates to use in examples.

Select the first n sequences from an alignment

Initialising take_n_seqs with the argument number=3 creates an app that returns the first 3 sequences from an alignment

Note

“first n” refers to the ordering in the fasta file.

Randomly selecting n sequences from an alignment

Using random=True and number=3 returns 3 random sequences. An optional argument for a seed can be provided to ensure the same sequences are returned each time the app is called.

Selecting the same sequences from multiple alignments

Providing the argument fixed_choice=True ensures the same sequences are returned when (randomly) sampling sequences across several alignments.