Prerequisites:

• Java JDK 1.8

Dependencies:

• JSON-Java

Description

This program computes the product of 2 matrices, using two different algorithms (SimpleMatrixMultiply, a naïve algorithm, and AdvancedMatrixMultiply, implementing the Strassen algorithm).

It takes the path to a JSON file containing 5 properties:

• height1 (height of the first matrix),
• width1 (width of the first matrix),
• height2 (height of the second matrix),
• width2 (width of the second matrix),
• seed (seed used to generate random numbers).

Then generates two matrices, fills them with random number using the provided seed, with bounds [-1000000;1000000], and finally computes the product of the two matrices in both ways (if possible).

Usage:

• Windows

javac -cp "src;libs/*" -d "out" src/*.java
java -Xmx8192m  -cp "out;libs/*" SimpleMatrixMultiply resources/matrices-4096-4095-4095-4096.json
java -Xmx8192m -cp "out;libs/*" AdvancedMatrixMultiply resources/matrices-4096-4095-4095-4096.json

• Linux

javac -cp "src:libs/*" -d "out" src/*.java
java -Xmx8192m  -cp "out:libs/*" SimpleMatrixMultiply resources/matrices-4096-4095-4095-4096.json
java -Xmx8192m -cp "out:libs/*" AdvancedMatrixMultiply resources/matrices-4096-4095-4095-4096.json

Note: all tests have been executed using -Xmx8192m (or -Xmx8192m for computers that don't have 8Go of RAM), allocating 8Go of heap size to the JVM.

Note on AdvancedMatrixMultiply: computing matrices with a side size of more than 4096 requires more than 8Go of RAM, in order not to exceed the JVM heap size.

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List of files to test on (in resources/):

• matrices-1-1-1-1.json
• matrices-5-2-20-5.json
• matrices-9-9-9-9.json
• matrices-15-10-10-5.json
• matrices-2000-3000-3000-2000.json
• matrices-3001-2001-2001-3001.json
• matrices-4000-4000-4000-4000.json
• matrices-4096-4095-4095-4096.json

Running the program with -v displays the 2 generated matrices and the 2 results m1 * m2 and m2 * m1

Results can be checked on (easier using the 4 first JSON files): http://wims.unice.fr/wims/wims.cgi?session=3ICB518C69.3&+lang=en&+module=tool%2Flinear%2Fmatmult

License

This software is under the MIT License (Copyright 2017, Adrien HARNAY).