b07lab1/Polynomial.java at main · Rose-sys-collan/b07lab1 · GitHub

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public class Polynomial {
    double[] coefficients;
    int[] expo;

    public Polynomial() {
        coefficients = new double[1];
        expo = new int[1];
        coefficients[0] = 0;
        expo[0] = 0;
    }

    public Polynomial(double[] nums, int[] expos) {
        coefficients = new double[nums.length];
        expo = new int[expos.length];
        for (int i=0; i<nums.length; i++)
        {
            coefficients[i] = nums[i];
        }
        for (int i=0; i<expos.length; i++)
        {
            expo[i] = expos[i];
        }
    }

    public Polynomial add(Polynomial poly) {
        int maxlen_co = Math.max(this.coefficients.length, poly.coefficients.length);
        double[] res_co = new double[maxlen_co];
        for (int i=0; i<this.coefficients.length; i++) {
            res_co[i] += this.coefficients[i];
        }
        for (int i=0; i<poly.coefficients.length; i++) {
            res_co[i] += poly.coefficients[i];
        }

        int maxlen_ex = Math.max(this.expo.length, poly.expo.length);
        int[] res_ex = new int[maxlen_ex];
        for (int i=0; i<this.expo.length; i++) {
            res_ex[i] += this.expo[i];
        }
        for (int i=0; i<poly.expo.length; i++) {
            res_ex[i] += poly.expo[i];
        }
        return new Polynomial(res_co, res_ex);
    }

    public double evaluate(double x) {
        double res = 0;
        for (int i=0; i<this.coefficients.length; i++ )
        {
            res += this.coefficients[i] * Math.pow(x, this.expo[i]);
        }
        return res;
    }

    public boolean hasRoot(double x) {
        return evaluate(x) == 0;
    }


    public Polynomial multiply(Polynomial poly) {
        double[] new_co;
        int[] new_ex;

        for(int i=0; i<this.coefficients.length; i++) {
            for(int j=0; j<poly.coefficients.length; j++) {

            }
        }
        return new Polynomial(new_co, new_ex);
    }


    public Polynomial(File file) {
        String regex = "[+\\-]";
        String[] item = file.split(regex);
        int l = item.length;

        coefficients = new double[l];
        expo = new int[l];

        for(int i=0; i<l; i++) {
            coefficients[i] = parseDouble(item[i], 10);
            expo[i] = parseInt(item[i], 10);
        }
    }

    public saveToFile(String s) {

    }
}