Converts raw phred quality scores into base-calling error probabilities.
@tf.function
tfio.genome.phred_sequences_to_probability( phred_qualities )
Used in the notebooks
For each ASCII encoded phred quality score (X), the probability that there was an error calling that base is computed by:
P = 10 ^ (-(X - 33) / 10)
This is assuming an "ASCII base" of 33.
The input is a tf.string tensor of ASCII encoded phred qualities, one string per DNA sequence, with each character representing the quality of a nucelotide.
For example:
phred_qualities = [["BB<"], ["BBBB"]]
Args | |
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phred_qualities
|
A tf.string tensor where each string represents the phred quality of a DNA sequence. Each character in the string is the ASCII representation of the phred quality number. |
Returns | |
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tf.RaggedTensor
|
The quality scores for each base in each sequence provided. |