程序包 edu.princeton.cs.algs4

类 Polynomial

  • public class Polynomial
extends java.lang.Object
    The Polynomial class represents a polynomial with integer coefficients. Polynomials are immutable: their values cannot be changed after they are created. It includes methods for addition, subtraction, multiplication, composition, differentiation, and evaluation.

    For additional documentation, see Section 9.9 of Algorithms, 4th Edition by Robert Sedgewick and Kevin Wayne.

    • 构造器概要

      构造器 
      构造器 说明
      Polynomial​(int a, int b)
      Initializes a new polynomial a x^b

    • 方法概要

      修饰符和类型 方法 说明
      int compareTo​(Polynomial that)
      Compares two polynomials by degree, breaking ties by coefficient of leading term.
      Polynomial compose​(Polynomial that)
      Returns the composition of this polynomial and the specified polynomial.
      int degree()
      Returns the degree of this polynomial.
      Polynomial differentiate()
      Returns the result of differentiating this polynomial.
      boolean equals​(java.lang.Object other)
      Compares this polynomial to the specified polynomial.
      int evaluate​(int x)
      Returns the result of evaluating this polynomial at the point x.
      static void main​(java.lang.String[] args)
      Unit tests the polynomial data type.
      Polynomial minus​(Polynomial that)
      Returns the result of subtracting the specified polynomial from this polynomial.
      Polynomial plus​(Polynomial that)
      Returns the sum of this polynomial and the specified polynomial.
      Polynomial times​(Polynomial that)
      Returns the product of this polynomial and the specified polynomial.
      java.lang.String toString()
      Return a string representation of this polynomial.

      • 从类继承的方法 java.lang.Object

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

    • 构造器详细资料

      • Polynomial

        public Polynomial​(int a,
                  int b)
        Initializes a new polynomial a x^b
        参数:
        a - the leading coefficient
        b - the exponent
        抛出:
        java.lang.IllegalArgumentException - if b is negative

    • 方法详细资料

      • degree

        public int degree()
        Returns the degree of this polynomial.
        返回:
        the degree of this polynomial, -1 for the zero polynomial.

      • plus

        public Polynomial plus​(Polynomial that)
        Returns the sum of this polynomial and the specified polynomial.
        参数:
        that - the other polynomial
        返回:
        the polynomial whose value is (this(x) + that(x))

      • minus

        public Polynomial minus​(Polynomial that)
        Returns the result of subtracting the specified polynomial from this polynomial.
        参数:
        that - the other polynomial
        返回:
        the polynomial whose value is (this(x) - that(x))

      • times

        public Polynomial times​(Polynomial that)
        Returns the product of this polynomial and the specified polynomial. Takes time proportional to the product of the degrees. (Faster algorithms are known, e.g., via FFT.)
        参数:
        that - the other polynomial
        返回:
        the polynomial whose value is (this(x) * that(x))

      • compose

        public Polynomial compose​(Polynomial that)
        Returns the composition of this polynomial and the specified polynomial. Takes time proportional to the product of the degrees. (Faster algorithms are known, e.g., via FFT.)
        参数:
        that - the other polynomial
        返回:
        the polynomial whose value is (this(that(x)))

      • equals

        public boolean equals​(java.lang.Object other)
        Compares this polynomial to the specified polynomial.
        覆盖:
        equals 在类中 java.lang.Object
        参数:
        other - the other polynoimal
        返回:
        true if this polynomial equals other; false otherwise

      • differentiate

        public Polynomial differentiate()
        Returns the result of differentiating this polynomial.
        返回:
        the polynomial whose value is this'(x)

      • evaluate

        public int evaluate​(int x)
        Returns the result of evaluating this polynomial at the point x.
        参数:
        x - the point at which to evaluate the polynomial
        返回:
        the integer whose value is (this(x))

      • compareTo

        public int compareTo​(Polynomial that)
        Compares two polynomials by degree, breaking ties by coefficient of leading term.
        参数:
        that - the other point
        返回:
        the value 0 if this polynomial is equal to the argument polynomial (precisely when equals() returns true); a negative integer if this polynomialt is less than the argument polynomial; and a positive integer if this polynomial is greater than the argument point

      • toString

        public java.lang.String toString()
        Return a string representation of this polynomial.
        覆盖:
        toString 在类中 java.lang.Object
        返回:
        a string representation of this polynomial in the format 4x^5 - 3x^2 + 11x + 5

      • main

        public static void main​(java.lang.String[] args)
        Unit tests the polynomial data type.
        参数:
        args - the command-line arguments (none)