Class BinSizer

java.lang.Object
uk.ac.starlink.ttools.plot2.layer.BinSizer

@Equality public abstract class BinSizer extends Object
Determines 1-d histogram bin widths from data bounds.
Since:
8 Jan 2014
Author:
Mark Taylor
  • Constructor Details

    • BinSizer

      public BinSizer()
  • Method Details

    • getWidth

      public abstract double getWidth(boolean xlog, double xlo, double xhi, Rounding rounding)
      Provides a bin width value for a given axis data range.
      Parameters:
      xlog - false for linear scaling, true for logarithmic
      xlo - axis lower bound
      xhi - axis upper bound
      rounding - rounding policy hint (may be ignored) or null for no rounding
      Returns:
      additive/multiplicative bin width appropriate for the given range
    • createFixedBinSizer

      public static BinSizer createFixedBinSizer(double binWidth)
      Returns a bin sizer instance which always returns the same fixed value. No rounding is performed.
      Parameters:
      binWidth - fixed bin width
      Returns:
      bin sizer
    • createCountBinSizer

      public static BinSizer createCountBinSizer(double nbin)
      Returns a bin sizer instance which divides the axis range up into an approximately fixed number of equal intervals. Rounding is performed on request, so that bin sizes are sensible values that give a bin count near the requested value.
      Parameters:
      nbin - number of intervals to divide the axis into
      Returns:
      bin sizer instance
    • createSizerConfigKey

      public static ConfigKey<BinSizer> createSizerConfigKey(ConfigMeta meta, ReportKey<Double> widthReportKey, int dfltNbin, boolean allowZero)
      Constructs a config key for acquiring BinSizers.
      Parameters:
      meta - key metadata
      widthReportKey - report key giving bin width in data coordinates
      dfltNbin - default bin count
      allowZero - true iff zero is an allowed width
      Returns:
      new config key
    • getConfigKeyDescription

      public static String getConfigKeyDescription()
      Returns an XML string describing in general terms how to operate the BinSizer config key.
      Returns:
      XML <p> element(s)