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21 lines
1.2 KiB
Markdown
21 lines
1.2 KiB
Markdown
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## BioSequence.Kmers(k int) — Semantic Description
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The `Kmers` method is a generator function that yields all contiguous *k*-length subsequences (called **k-mers**) from a biological sequence (`BioSequence`).
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- It operates on `[]byte` data, assuming the underlying sequence is stored as a byte slice (e.g., DNA bases `A`, `C`, `G`, `T`).
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- Uses Go’s new iterator protocol (`iter.Seq[[]byte]`) for memory-efficient, lazy evaluation.
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- Validates input: returns an empty iterator if `k ≤ 0` or exceeds sequence length.
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- Iterates linearly from index `i = 0` to `len(seq) - k`, extracting slices of length *k*.
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- Each yielded value is a **non-copying slice view** (efficient, but mutable if original data changes).
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- Supports early termination: the consumer can stop iteration by returning `false` from the yield callback.
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- Designed for downstream tasks like sequence analysis, motif discovery, or hashing (e.g., in k-mer counting).
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- Does *not* handle reverse-complement or ambiguous bases—assumes raw sequence input.
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Usage example:
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```go
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for kmer := range seq.Kmers(3) {
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fmt.Printf("%s\n", string(kmer))
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}
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```
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This yields all 3-mers (e.g., `"ACG"`, `"CGT"`...) in order.
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