Counting nucleotides from a sequence

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Counting nucleotides from a sequence

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Last edited Oct 27, 2015

Created on Oct 27, 2015

This example shows how to calculate the percentage of G and C nucleotides in a DNA sequence, a common metric in genomics. It first counts each nucleotide type (A, C, G, T) using a Python dictionary, then normalizes those counts by the total sequence length to compute percentages. The code defines two functions, `count_nucleotides_by_type` and `normalize_nucleotide_count`, and finally prints the combined G and C percentage for a hardcoded sequence string. No external visualization libraries are used; the output is a single text result.

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