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PO.equals() not evaluating to proper boolean
 

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  1. PO.equals() not evaluating to proper boolean
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    <pre><code>public class SparseMatrix { private final TreeMap&lt;Integer,TreeMap&lt;Integer,Double&gt;&gt; matrix; private final int rows; private final int cols; public SparseMatrix(int r, int c) { // Creates instances for matrix objects this.matrix = new TreeMap&lt;&gt;(); // Assigns the matrix a number of rows and a number of columns this.rows = r; this.cols = c; } public TreeMap&lt;Integer, TreeMap&lt;Integer, Double&gt;&gt; getMatrix() { return matrix; } public static boolean equals(SparseMatrix a, SparseMatrix b) { if (a.getMatrix().equals(b.getMatrix()) == true) { return true; } else { return false; } } } </code></pre> <p>Keys and values are inputted by the user then there's a test driver to make sure it works right, but it's not evaluating the matrices right. It tells me true every time. I'm assuming it's the == true and the equals comparator. It returns true if all the keys and values of both matrices are equal.</p> <p>"new" command: </p> <pre><code>if (cmd.equals("new")) { String name = input.next(); int rows = input.nextInt(); int cols = input.nextInt(); if (rows &lt; 1 || cols &lt; 1) { System.out.println("new: rows and/or cols less than 1: "); System.exit(1); } SparseMatrix m = new SparseMatrix(rows,cols); int i = input.nextInt(); while (i &gt;= 0) { int j = input.nextInt(); double v = input.nextDouble(); m.set(i,j,v); i = input.nextInt(); } matrix.put(name,m); System.out.printf("new %s = %s\n", name, m); } </code></pre> <p>The test driver part is:</p> <pre><code>String a = input.next(); if (!matrix.containsKey(a)) { System.out.println("equals: no such matrix: " + a); System.exit(1); } String b = input.next(); if (!matrix.containsKey(b)) { System.out.println("equals: no such matrix: " + b); System.exit(1); } System.out.printf("%s.equals(%s) = %b\n", a, b, SparseMatrix.equals(matrix.get(a),matrix.get(b))); </code></pre> <p>And the input looks like:</p> <pre><code>new name1 10 10 // new matrix with 10 rows and 10 columns 10 10 10.0 // int int double treemap -1 // stops the input </code></pre>
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    1. PTQuestion
    1. USChilledrat
    1. USuser2958542
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      1. PO.equals() not evaluating to proper boolean
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    2. VO
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      1. VTUpMod
    1. COCan we also see your test cases that are always returning true?
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      1. UShankd
    2. COIs that all of the code? If so, then it would always return true because matrix is always just an empty tree map. Presumably there's more code involved (you mention user input); you need to provide more of the code to enable insight into a solution,
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      1. USuser1676075
    3. COCode added for this! ^
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      1. USuser2958542
 

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