int main (int argc, const char * argv[])
{
typedef float ScalarType; //feel free to change this to 'double' if supported by your hardware
typedef boost::numeric::ublas::vector<ScalarType> VectorType;
typedef viennacl::vector<ScalarType> VCLVectorType;
std::size_t dim_large = 7;
std::size_t dim_small = 3;
//
// Setup ublas objects and fill with data:
//
VectorType ublas_v1(dim_large);
VectorType ublas_v2(dim_small);
for (std::size_t i=0; i<ublas_v1.size(); ++i)
ublas_v1(i) = i+1;
for (std::size_t i=0; i<ublas_v2.size(); ++i)
ublas_v2(i) = dim_large + i;
//
// Extract submatrices using the ranges in ublas
//
boost::numeric::ublas::range ublas_r1(0, dim_small); //the first 'dim_small' entries
boost::numeric::ublas::range ublas_r2(dim_small - 1, 2*dim_small - 1); // 'dim_small' entries somewhere from the middle
boost::numeric::ublas::range ublas_r3(dim_large - dim_small, dim_large); // the last 'dim_small' entries
boost::numeric::ublas::vector_range<VectorType> ublas_v1_sub1(ublas_v1, ublas_r1); // front part of vector v_1
boost::numeric::ublas::vector_range<VectorType> ublas_v1_sub2(ublas_v1, ublas_r2); // center part of vector v_1
boost::numeric::ublas::vector_range<VectorType> ublas_v1_sub3(ublas_v1, ublas_r3); // tail of vector v_1
//
// Setup ViennaCL objects
//
VCLVectorType vcl_v1(dim_large);
VCLVectorType vcl_v2(dim_small);
viennacl::copy(ublas_v1, vcl_v1);
viennacl::copy(ublas_v2, vcl_v2);
//
// Extract submatrices using the ranges in ViennaCL
//
viennacl::range vcl_r1(0, dim_small); //the first 'dim_small' entries
viennacl::range vcl_r2(dim_small - 1, 2*dim_small - 1); // 'dim_small' entries somewhere from the middle
viennacl::range vcl_r3(dim_large - dim_small, dim_large); // the last 'dim_small' entries
viennacl::vector_range<VCLVectorType> vcl_v1_sub1(vcl_v1, vcl_r1); // front part of vector v_1
viennacl::vector_range<VCLVectorType> vcl_v1_sub2(vcl_v1, vcl_r2); // center part of vector v_1
viennacl::vector_range<VCLVectorType> vcl_v1_sub3(vcl_v1, vcl_r3); // tail of vector v_1
//
// Copy from ublas to submatrices and back:
//
ublas_v1_sub1 = ublas_v2;
viennacl::copy(ublas_v2, vcl_v1_sub1);
viennacl::copy(vcl_v1_sub1, ublas_v2);
//
// Addition:
//
ublas_v1_sub1 += ublas_v1_sub1;
vcl_v1_sub1 += vcl_v1_sub1;
ublas_v1_sub2 += ublas_v1_sub2;
vcl_v1_sub2 += vcl_v1_sub2;
ublas_v1_sub3 += ublas_v1_sub3;
vcl_v1_sub3 += vcl_v1_sub3;
//
// print vectors:
//
std::cout << "ublas: " << ublas_v1 << std::endl;
std::cout << "ViennaCL: " << vcl_v1 << std::endl;
//
// That's it.
//
std::cout << "!!!! TUTORIAL COMPLETED SUCCESSFULLY !!!!" << std::endl;
return EXIT_SUCCESS;
}
/**
* In the main() routine a couple of vectors from both Boost.uBLAS and ViennaCL are set up.
* Then, subvectors are extracted and manipulated using the usual operator overloads.
**/
int main (int, const char **)
{
//feel free to change the floating point type to 'double' if supported by your hardware
typedef float ScalarType;
typedef boost::numeric::ublas::vector<ScalarType> VectorType;
typedef viennacl::vector<ScalarType> VCLVectorType;
std::size_t dim_large = 7;
std::size_t dim_small = 3;
/**
* Setup ublas objects and fill with data:
**/
VectorType ublas_v1(dim_large);
VectorType ublas_v2(dim_small);
for (std::size_t i=0; i<ublas_v1.size(); ++i)
ublas_v1(i) = ScalarType(i+1);
for (std::size_t i=0; i<ublas_v2.size(); ++i)
ublas_v2(i) = ScalarType(dim_large + i);
/**
* Extract submatrices using the ranges in ublas
**/
boost::numeric::ublas::range ublas_r1(0, dim_small); //the first 'dim_small' entries
boost::numeric::ublas::range ublas_r2(dim_small - 1, 2*dim_small - 1); // 'dim_small' entries somewhere from the middle
boost::numeric::ublas::range ublas_r3(dim_large - dim_small, dim_large); // the last 'dim_small' entries
boost::numeric::ublas::vector_range<VectorType> ublas_v1_sub1(ublas_v1, ublas_r1); // front part of vector v_1
boost::numeric::ublas::vector_range<VectorType> ublas_v1_sub2(ublas_v1, ublas_r2); // center part of vector v_1
boost::numeric::ublas::vector_range<VectorType> ublas_v1_sub3(ublas_v1, ublas_r3); // tail of vector v_1
/**
* Create ViennaCL objects and copy data over from uBLAS objects.
**/
VCLVectorType vcl_v1(dim_large);
VCLVectorType vcl_v2(dim_small);
viennacl::copy(ublas_v1, vcl_v1);
viennacl::copy(ublas_v2, vcl_v2);
/**
* Extract submatrices using the range-functionality in ViennaCL. This works exactly the same way as for uBLAS.
**/
viennacl::range vcl_r1(0, dim_small); //the first 'dim_small' entries
viennacl::range vcl_r2(dim_small - 1, 2*dim_small - 1); // 'dim_small' entries somewhere from the middle
viennacl::range vcl_r3(dim_large - dim_small, dim_large); // the last 'dim_small' entries
viennacl::vector_range<VCLVectorType> vcl_v1_sub1(vcl_v1, vcl_r1); // front part of vector v_1
viennacl::vector_range<VCLVectorType> vcl_v1_sub2(vcl_v1, vcl_r2); // center part of vector v_1
viennacl::vector_range<VCLVectorType> vcl_v1_sub3(vcl_v1, vcl_r3); // tail of vector v_1
/**
* Copy from ublas to submatrices and back:
**/
ublas_v1_sub1 = ublas_v2;
viennacl::copy(ublas_v2, vcl_v1_sub1);
viennacl::copy(vcl_v1_sub1, ublas_v2);
/**
* Addition of subvectors:
**/
ublas_v1_sub1 += ublas_v1_sub1;
vcl_v1_sub1 += vcl_v1_sub1;
ublas_v1_sub2 += ublas_v1_sub2;
vcl_v1_sub2 += vcl_v1_sub2;
ublas_v1_sub3 += ublas_v1_sub3;
vcl_v1_sub3 += vcl_v1_sub3;
/**
* Print full vectors. Notice that the various entries have changed according to the subvector manipulations above.
**/
std::cout << "ublas: " << ublas_v1 << std::endl;
std::cout << "ViennaCL: " << vcl_v1 << std::endl;
/**
* That's it. Print success message and exit.
**/
std::cout << "!!!! TUTORIAL COMPLETED SUCCESSFULLY !!!!" << std::endl;
return EXIT_SUCCESS;
}