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copied!<p>Consider using Blitz++ instead. I tried out Blitz, and its performance is on par with C-style array! </p> <p>Check out your code with Blitz added below:</p> <hr> <pre><code>#include <windows.h> #define _SCL_SECURE_NO_WARNINGS #define BOOST_DISABLE_ASSERTS #include <boost/multi_array.hpp> #include <blitz/array.h> int main(int argc, char* argv[]) { const int X_SIZE = 200; const int Y_SIZE = 200; const int ITERATIONS = 500; unsigned int startTime = 0; unsigned int endTime = 0; // Create the boost array typedef boost::multi_array<double, 2> ImageArrayType; ImageArrayType boostMatrix(boost::extents[X_SIZE][Y_SIZE]); //------------------Measure boost---------------------------------------------- startTime = ::GetTickCount(); for (int i = 0; i < ITERATIONS; ++i) { for (int y = 0; y < Y_SIZE; ++y) { for (int x = 0; x < X_SIZE; ++x) { boostMatrix[x][y] = 2.345; } } } endTime = ::GetTickCount(); printf("[Boost] Elapsed time: %6.3f seconds\n", (endTime - startTime) / 1000.0); //------------------Measure blitz----------------------------------------------- blitz::Array<double, 2> blitzArray( X_SIZE, Y_SIZE ); startTime = ::GetTickCount(); for (int i = 0; i < ITERATIONS; ++i) { for (int y = 0; y < Y_SIZE; ++y) { for (int x = 0; x < X_SIZE; ++x) { blitzArray(x,y) = 2.345; } } } endTime = ::GetTickCount(); printf("[Blitz] Elapsed time: %6.3f seconds\n", (endTime - startTime) / 1000.0); //------------------Measure native----------------------------------------------- // Create the native array double *nativeMatrix = new double [X_SIZE * Y_SIZE]; startTime = ::GetTickCount(); for (int i = 0; i < ITERATIONS; ++i) { for (int y = 0; y < Y_SIZE; ++y) { for (int x = 0; x < X_SIZE; ++x) { nativeMatrix[x + (y * X_SIZE)] = 2.345; } } } endTime = ::GetTickCount(); printf("[Native]Elapsed time: %6.3f seconds\n", (endTime - startTime) / 1000.0); return 0; } </code></pre> <hr> <p>Here's the result in debug and release.</p> <p>DEBUG: </p> <pre><code>Boost 2.093 secs Blitz 0.375 secs Native 0.078 secs </code></pre> <p>RELEASE:</p> <pre><code>Boost 0.266 secs Blitz 0.016 secs Native 0.015 secs </code></pre> <p>I used MSVC 2008 SP1 compiler for this.</p> <p>Can we now say good-bye to C-stlye array? =p</p>

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