Class: BioReadQualityStatistics

Plot fractions of reads with Phred scores in ranges


H = plotPerPositionCountByQuality(QSObj)


plotPerPositionCountByQuality(QSObj) generates a line plot displaying the fractions of all reads that have Phred scores in the ranges of 0–10, 11–20, 21–30, and 31–40 at each base position for the BioReadQualityStatistics object QSObj.

H = plotPerPositionCountByQuality(QSObj) returns the handle H to the axes object containing the generated plot.

Input Arguments


BioReadQualityStatistics object.

Output Arguments


Handle to axes object containing generated plot.


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Plot Fractions of Reads Stratified by Phread Scores

Create a BioReadQualityStatistics object from a FASTQ file using only the first 40 characters of each read with a minimum average quality score of 5.

QSObj = BioReadQualityStatistics('SRR005164_1_50.fastq','FilterLength',40,...

Plot the fractions of all reads with Phred scores in the ranges of 0�10, 11�20, 21�30, and 31�40 at each base position.

ans = 

  Axes (Quality Stratification) with properties:

             XLim: [0.1000 41]
             YLim: [0 100]
           XScale: 'linear'
           YScale: 'linear'
    GridLineStyle: '-'
         Position: [0.1300 0.1100 0.7750 0.8150]
            Units: 'normalized'

  Use GET to show all properties

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