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    phred

    1.0.1 • Public • Published

    phred

    NPM

    Build Status

    convert phred quality scores to and from other numerical representations

    Overview

    Phred quality scores are a humanized representation of small error probabilities. They have a long history of use in genomics, where they have been employed to represent the quality of sequencing observations.

    If the probability of error is P, the phred quality score Q is defined as Q = -10 * log10(P).

    q to p

    Inversely, P = 10^(-Q/10):

    p to q

    This library encapsulates conversions between error probabilities and phred scores.

    Installation

    npm install phred
    

    Usage

    A Phred object is provided that allows for manipulation of quality scores.

    var Phred = require('phred')
     
    // print the phred to probability mapping
    [0,10,20,30,40,50].forEach(function(x) {
        var p = new Phred().fromQuality(x)
        console.log(x, p.toProb())
        })
    /* 
    0 1
    10 0.1
    20 0.01
    30 0.001
    40 0.0001
    50 0.00001
    */

    License

    MIT

    Install

    npm i phred

    DownloadsWeekly Downloads

    1

    Version

    1.0.1

    License

    MIT

    Last publish

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