edu.jas.root
Class RootUtil

java.lang.Object
  edu.jas.root.RootUtil

public class RootUtil
extends java.lang.Object

Real root utilities. For example real root count.

Author:

Heinz Kredel

Constructor Summary

RootUtil()

Method Summary

static <C extends RingElem<C> & Rational> Interval<C>	parseInterval(RingFactory<C> fac, java.lang.String s) Parse interval for a real root from String.
static <C extends RingElem<C> & Rational> Rectangle<C>	parseRectangle(RingFactory<Complex<C>> fac, java.lang.String s) Parse rectangle for a complex root from String.
static <C extends RingElem<C>> long	signVar(java.util.List<C> L) Count changes in sign.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

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> & Rational> Interval<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> & Rational> Rectangle<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.