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/* |
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* Written by Doug Lea with assistance from members of JCP JSR-166 |
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* Expert Group and released to the public domain, as explained at |
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* http://creativecommons.org/licenses/publicdomain |
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* http://creativecommons.org/publicdomain/zero/1.0/ |
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*/ |
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// Jacobi iteration on a mesh. Based loosely on a Filaments demo |
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public class FJJacobi { |
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static final int DEFAULT_GRANULARITY = 4096; // 1024; |
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// static final int DEFAULT_GRANULARITY = 4096; |
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static final int DEFAULT_GRANULARITY = 256; |
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/** |
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* The maximum number of matrix cells |
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* at which to stop recursing down and instead directly update. |
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**/ |
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*/ |
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static final double EPSILON = 0.0001; // convergence criterion |
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public static void main(String[] args) throws Exception { |
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return; |
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} |
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ForkJoinPool fjp = new ForkJoinPool(); |
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// ForkJoinPool fjp = new ForkJoinPool(1); |
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ForkJoinPool fjp = ForkJoinPool.commonPool(); |
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// allocate enough space for edges |
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int dim = n+2; |
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System.out.println("Compute Time: " + secs); |
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System.out.println(fjp); |
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Thread.sleep(1000); |
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} |
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} |
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abstract static class MatrixTree extends RecursiveAction { |
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// maximum difference between old and new values |
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double maxDiff; |
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reinitialize(); |
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} |
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double m = maxDiff; |
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return (md > m)? md : m; |
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return (md > m) ? md : m; |
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} |
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} |
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static final class LeafNode extends MatrixTree { |
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final double[][] A; // matrix to get old values from |
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final double[][] B; // matrix to put new values into |
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public void compute() { |
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boolean AtoB = (steps++ & 1) == 0; |
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double[][] a = (AtoB)? A : B; |
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double[][] b = (AtoB)? B : A; |
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double[][] a = AtoB ? A : B; |
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double[][] b = AtoB ? B : A; |
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double md = 0.0; // local for computing max diff |
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} |
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} |
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static final class TwoNode extends MatrixTree { |
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final MatrixTree q1; |
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final MatrixTree q2; |
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} |
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static final class Driver extends RecursiveAction { |
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MatrixTree mat; |
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double[][] A; double[][] B; |
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System.out.println("max diff after " + steps + " steps = " + md); |
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} |
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} |
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} |