本文整理汇总了C++中viennacl::matrix_base::row_major方法的典型用法代码示例。如果您正苦于以下问题：C++ matrix_base::row_major方法的具体用法？C++ matrix_base::row_major怎么用？C++ matrix_base::row_major使用的例子？那么, 这里精选的方法代码示例或许可以为您提供帮助。您也可以进一步了解该方法所在类viennacl::matrix_base的用法示例。
在下文中一共展示了matrix_base::row_major方法的1个代码示例，这些例子默认根据受欢迎程度排序。您可以为喜欢或者感觉有用的代码点赞，您的评价将有助于系统推荐出更棒的C++代码示例。
示例1: nmf
void nmf(viennacl::matrix_base<NumericT> const & V,
viennacl::matrix_base<NumericT> & W,
viennacl::matrix_base<NumericT> & H,
viennacl::linalg::nmf_config const & conf)
{
viennacl::hsa::context & ctx = const_cast<viennacl::hsa::context &>(viennacl::traits::hsa_context(V));
const std::string NMF_MUL_DIV_KERNEL = "el_wise_mul_div";
viennacl::linalg::opencl::kernels::nmf<NumericT, viennacl::hsa::context>::init(ctx);
vcl_size_t k = W.size2();
conf.iters_ = 0;
if (viennacl::linalg::norm_frobenius(W) <= 0)
W = viennacl::scalar_matrix<NumericT>(W.size1(), W.size2(), NumericT(1), ctx);
if (viennacl::linalg::norm_frobenius(H) <= 0)
H = viennacl::scalar_matrix<NumericT>(H.size1(), H.size2(), NumericT(1), ctx);
viennacl::matrix_base<NumericT> wn(V.size1(), k, W.row_major(), ctx);
viennacl::matrix_base<NumericT> wd(V.size1(), k, W.row_major(), ctx);
viennacl::matrix_base<NumericT> wtmp(V.size1(), V.size2(), W.row_major(), ctx);
viennacl::matrix_base<NumericT> hn(k, V.size2(), H.row_major(), ctx);
viennacl::matrix_base<NumericT> hd(k, V.size2(), H.row_major(), ctx);
viennacl::matrix_base<NumericT> htmp(k, k, H.row_major(), ctx);
viennacl::matrix_base<NumericT> appr(V.size1(), V.size2(), V.row_major(), ctx);
NumericT last_diff = 0;
NumericT diff_init = 0;
bool stagnation_flag = false;
for (vcl_size_t i = 0; i < conf.max_iterations(); i++)
{
conf.iters_ = i + 1;
{
hn = viennacl::linalg::prod(trans(W), V);
htmp = viennacl::linalg::prod(trans(W), W);
hd = viennacl::linalg::prod(htmp, H);
viennacl::hsa::kernel & mul_div_kernel = ctx.get_kernel(viennacl::linalg::opencl::kernels::nmf<NumericT>::program_name(), NMF_MUL_DIV_KERNEL);
viennacl::hsa::enqueue(mul_div_kernel(H, hn, hd, cl_uint(H.internal_size1() * H.internal_size2())));
}
{
wn = viennacl::linalg::prod(V, trans(H));
wtmp = viennacl::linalg::prod(W, H);
wd = viennacl::linalg::prod(wtmp, trans(H));
viennacl::hsa::kernel & mul_div_kernel = ctx.get_kernel(viennacl::linalg::opencl::kernels::nmf<NumericT>::program_name(), NMF_MUL_DIV_KERNEL);
viennacl::hsa::enqueue(mul_div_kernel(W, wn, wd, cl_uint(W.internal_size1() * W.internal_size2())));
}
if (i % conf.check_after_steps() == 0) //check for convergence
{
appr = viennacl::linalg::prod(W, H);
appr -= V;
NumericT diff_val = viennacl::linalg::norm_frobenius(appr);
if (i == 0)
diff_init = diff_val;
if (conf.print_relative_error())
std::cout << diff_val / diff_init << std::endl;
// Approximation check
if (diff_val / diff_init < conf.tolerance())
break;
// Stagnation check
if (std::fabs(diff_val - last_diff) / (diff_val * NumericT(conf.check_after_steps())) < conf.stagnation_tolerance()) //avoid situations where convergence stagnates
{
if (stagnation_flag) // iteration stagnates (two iterates with no notable progress)
break;
else
// record stagnation in this iteration
stagnation_flag = true;
} else
// good progress in this iteration, so unset stagnation flag
stagnation_flag = false;
// prepare for next iterate:
last_diff = diff_val;
}
}
}