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POCreating a polynomial from Int text file.
 

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  1. POCreating a polynomial from Int text file.
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    <p>I'm reading in a .txt file to create polynomials. I am having trouble actually printing the polynomials (after they've been put into the linked list). I'm not really sure how to go about 'linking' the linked list and the polynomial method... </p> <p>Text File: </p> <pre><code>P1 = 3 5 1 -1 0 8 P2 = 5 6 2 -1 1 7 0 -4 p3 = p1 + p2 p4 = p3 - p1 </code></pre> <p>Code: </p> <pre><code>import java.io.File; import java.io.FileInputStream; import java.io.FileNotFoundException; import java.io.IOException; import java.util.Iterator; import java.util.LinkedList; import java.util.Scanner; public class Polynomial { public Term first; public Term last; private int[] coef; // coefficients private int deg; // degree of polynomial (0 for the zero polynomial) // a * x^b public Polynomial(int a, int b) { coef = new int[b + 1]; coef[b] = a; deg = degree(); } // return the degree of this polynomial (0 for the zero polynomial) public int degree() { int d = 0; for (int i = 0; i &lt; coef.length; i++) if (coef[i] != 0) d = i; return d; } // return c = a + b public Polynomial plus(Polynomial b) { Polynomial a = this; Polynomial c = new Polynomial(0, Math.max(a.deg, b.deg)); for (int i = 0; i &lt;= a.deg; i++) c.coef[i] += a.coef[i]; for (int i = 0; i &lt;= b.deg; i++) c.coef[i] += b.coef[i]; c.deg = c.degree(); return c; } // return (a - b) public Polynomial minus(Polynomial b) { Polynomial a = this; Polynomial c = new Polynomial(0, Math.max(a.deg, b.deg)); for (int i = 0; i &lt;= a.deg; i++) c.coef[i] += a.coef[i]; for (int i = 0; i &lt;= b.deg; i++) c.coef[i] -= b.coef[i]; c.deg = c.degree(); return c; } // convert to string representation public String toString() { if (deg == 0) return "" + coef[0]; if (deg == 1) return coef[1] + "x + " + coef[0]; String s = coef[deg] + "x^" + deg; for (int i = deg - 1; i &gt;= 0; i--) { if (coef[i] == 0) continue; else if (coef[i] &gt; 0) s = s + " + " + (coef[i]); else if (coef[i] &lt; 0) s = s + " - " + (-coef[i]); if (i == 1) s = s + "x"; else if (i &gt; 1) s = s + "x^" + i; } return s; } // test client public static void main(String[] args) throws IOException { // Welcome message System.out .println("Welcome! The following program processes single-variable polynomials represented as linked lists.\n" + "Test Data will appear below, and is also saved to a text file (userSpecification.txt) \n" + "-------------------------------" + "\n"); String content = new String(); String name = new String(); File file = new File("polynomialTest.txt"); LinkedList&lt;String&gt; list = new LinkedList&lt;String&gt;(); try { Scanner sc = new Scanner(new FileInputStream(file)); while (sc.hasNext()) { name = sc.next(); content = sc.nextLine(); // ..just checking things as they come in. System.out.println("name " + name + " content " + content); list.add(content); } sc.close(); } catch (FileNotFoundException fnfe) { fnfe.printStackTrace(); } catch (Exception e) { e.printStackTrace(); System.out.println("\nProgram terminated Safely..."); } Iterator&lt;String&gt; i = list.iterator(); while (i.hasNext()) { System.out.println(name + i.next() + "\n"); } private class Term { int coef; int expo; Term next; Term(int coef, int expo, Term n) { this.coef = coef; this.expo = expo; this.next = n; } } } </code></pre> <p>Desired output: </p> <pre><code>P1 = 5X^3 – 4X + 8 P2 = 6X^5 -2X^2 +7X -4 P3 = 6X^5 +5X^3 -2X^2 +3X +4 P4 = 6X^5 -2X^2 +7X -4 </code></pre> <p>Output right now: </p> <pre><code>Project #2 Welcome! The following program processes single-variable polynomials represented as linked lists. ------------------------------- P1 = 3 5 1 -1 0 8 P2 = 5 6 2 -1 1 7 0 -4 p3 = p1 + p2 p4 = p3 - p1 [P1 = 3 5 1 -1 0 8, P2 = 5 6 2 -1 1 7 0 -4, p3 = p1 + p2, p4 = p3 - p1] </code></pre>
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    1. UStommy1370
    1. UStommy1370
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    1. COIt must be: P1 = 5X^3 - X + 8, your first equation is incorrect, or your input data is incorrect.
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      1. POCreating a polynomial from Int text file.
      1. USeternaln00b
    2. COThanks, I'm not so much worried about the number as I am getting the polynomials to actually display (like the expected output). Good catch though, I'll change that!
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      1. POCreating a polynomial from Int text file.
      1. UStommy1370
 

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