Package edu.jas.root

Class RootUtil


  • public class RootUtil
    extends java.lang.Object
    Real root utilities. For example real root count.
    • Field Summary

      Fields 
      Modifier and Type Field Description
      private static boolean debug  
      private static org.apache.logging.log4j.Logger logger  
    • Constructor Summary

      Constructors 
      Constructor Description
      RootUtil()  
    • Field Detail

      • logger

        private static final org.apache.logging.log4j.Logger logger
      • debug

        private static final boolean debug
    • Constructor Detail

      • RootUtil

        public RootUtil()
    • Method Detail

      • signVar

        public static <C extends RingElem<C>> long signVar​(java.util.List<C> L)
        Count changes in sign.
        Type Parameters:
        C - coefficient type.
        Parameters:
        L - list of coefficients.
        Returns:
        number of sign changes in L.
      • parseInterval

        public static <C extends RingElem<C> & RationalInterval<C> parseInterval​(RingFactory<C> fac,
                                                                                   java.lang.String s)
        Parse interval for a real root from String.
        Parameters:
        s - String, syntax: [left, right] or [mid].
        Returns:
        Interval from s.
      • parseRectangle

        public static <C extends RingElem<C> & RationalRectangle<C> parseRectangle​(RingFactory<Complex<C>> fac,
                                                                                     java.lang.String s)
        Parse rectangle for a complex root from String.
        Parameters:
        s - String, syntax: [south-west, north-east] or [mid].
        Returns:
        Interval from s.