diff options
author | Nao Pross <np@0hm.ch> | 2024-02-12 14:52:43 +0100 |
---|---|---|
committer | Nao Pross <np@0hm.ch> | 2024-02-12 14:52:43 +0100 |
commit | eda5bc26f44ee9a6f83dcf8c91f17296d7fc509d (patch) | |
tree | bc2efa38ff4e350f9a111ac87065cd7ae9a911c7 /src/armadillo/include/armadillo_bits/spop_var_meat.hpp | |
download | fsisotool-eda5bc26f44ee9a6f83dcf8c91f17296d7fc509d.tar.gz fsisotool-eda5bc26f44ee9a6f83dcf8c91f17296d7fc509d.zip |
Move into version control
Diffstat (limited to 'src/armadillo/include/armadillo_bits/spop_var_meat.hpp')
-rw-r--r-- | src/armadillo/include/armadillo_bits/spop_var_meat.hpp | 414 |
1 files changed, 414 insertions, 0 deletions
diff --git a/src/armadillo/include/armadillo_bits/spop_var_meat.hpp b/src/armadillo/include/armadillo_bits/spop_var_meat.hpp new file mode 100644 index 0000000..8d01a44 --- /dev/null +++ b/src/armadillo/include/armadillo_bits/spop_var_meat.hpp @@ -0,0 +1,414 @@ +// SPDX-License-Identifier: Apache-2.0 +// +// Copyright 2008-2016 Conrad Sanderson (http://conradsanderson.id.au) +// Copyright 2008-2016 National ICT Australia (NICTA) +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. +// ------------------------------------------------------------------------ + + +//! \addtogroup spop_var +//! @{ + + + +template<typename T1> +inline +void +spop_var::apply(SpMat<typename T1::pod_type>& out, const mtSpOp<typename T1::pod_type, T1, spop_var>& in) + { + arma_extra_debug_sigprint(); + + //typedef typename T1::elem_type in_eT; + typedef typename T1::pod_type out_eT; + + const uword norm_type = in.aux_uword_a; + const uword dim = in.aux_uword_b; + + arma_debug_check( (norm_type > 1), "var(): parameter 'norm_type' must be 0 or 1" ); + arma_debug_check( (dim > 1), "var(): parameter 'dim' must be 0 or 1" ); + + const SpProxy<T1> p(in.m); + + if(p.is_alias(out) == false) + { + spop_var::apply_noalias(out, p, norm_type, dim); + } + else + { + SpMat<out_eT> tmp; + + spop_var::apply_noalias(tmp, p, norm_type, dim); + + out.steal_mem(tmp); + } + } + + + +template<typename T1> +inline +void +spop_var::apply_noalias + ( + SpMat<typename T1::pod_type>& out, + const SpProxy<T1>& p, + const uword norm_type, + const uword dim + ) + { + arma_extra_debug_sigprint(); + + typedef typename T1::elem_type in_eT; + //typedef typename T1::pod_type out_eT; + + const uword p_n_rows = p.get_n_rows(); + const uword p_n_cols = p.get_n_cols(); + + // TODO: this is slow; rewrite based on the approach used by sparse mean() + + if(dim == 0) // find variance in each column + { + arma_extra_debug_print("spop_var::apply_noalias(): dim = 0"); + + out.set_size((p_n_rows > 0) ? 1 : 0, p_n_cols); + + if( (p_n_rows == 0) || (p.get_n_nonzero() == 0) ) { return; } + + for(uword col = 0; col < p_n_cols; ++col) + { + if(SpProxy<T1>::use_iterator) + { + // We must use an iterator; we can't access memory directly. + typename SpProxy<T1>::const_iterator_type it = p.begin_col(col); + typename SpProxy<T1>::const_iterator_type end = p.begin_col(col + 1); + + const uword n_zero = p_n_rows - (end.pos() - it.pos()); + + // in_eT is used just to get the specialization right (complex / noncomplex) + out.at(0, col) = spop_var::iterator_var(it, end, n_zero, norm_type, in_eT(0)); + } + else + { + // We can use direct memory access to calculate the variance. + out.at(0, col) = spop_var::direct_var + ( + &p.get_values()[p.get_col_ptrs()[col]], + p.get_col_ptrs()[col + 1] - p.get_col_ptrs()[col], + p_n_rows, + norm_type + ); + } + } + } + else + if(dim == 1) // find variance in each row + { + arma_extra_debug_print("spop_var::apply_noalias(): dim = 1"); + + out.set_size(p_n_rows, (p_n_cols > 0) ? 1 : 0); + + if( (p_n_cols == 0) || (p.get_n_nonzero() == 0) ) { return; } + + for(uword row = 0; row < p_n_rows; ++row) + { + // We have to use an iterator here regardless of whether or not we can + // directly access memory. + typename SpProxy<T1>::const_row_iterator_type it = p.begin_row(row); + typename SpProxy<T1>::const_row_iterator_type end = p.end_row(row); + + const uword n_zero = p_n_cols - (end.pos() - it.pos()); + + out.at(row, 0) = spop_var::iterator_var(it, end, n_zero, norm_type, in_eT(0)); + } + } + } + + + +template<typename T1> +inline +typename T1::pod_type +spop_var::var_vec + ( + const T1& X, + const uword norm_type + ) + { + arma_extra_debug_sigprint(); + + arma_debug_check( (norm_type > 1), "var(): parameter 'norm_type' must be 0 or 1" ); + + // conditionally unwrap it into a temporary and then directly operate. + + const unwrap_spmat<T1> tmp(X); + + return direct_var(tmp.M.values, tmp.M.n_nonzero, tmp.M.n_elem, norm_type); + } + + + +template<typename eT> +inline +eT +spop_var::direct_var + ( + const eT* const X, + const uword length, + const uword N, + const uword norm_type + ) + { + arma_extra_debug_sigprint(); + + if(length >= 2 && N >= 2) + { + const eT acc1 = spop_mean::direct_mean(X, length, N); + + eT acc2 = eT(0); + eT acc3 = eT(0); + + uword i, j; + + for(i = 0, j = 1; j < length; i += 2, j += 2) + { + const eT Xi = X[i]; + const eT Xj = X[j]; + + const eT tmpi = acc1 - Xi; + const eT tmpj = acc1 - Xj; + + acc2 += tmpi * tmpi + tmpj * tmpj; + acc3 += tmpi + tmpj; + } + + if(i < length) + { + const eT Xi = X[i]; + + const eT tmpi = acc1 - Xi; + + acc2 += tmpi * tmpi; + acc3 += tmpi; + } + + // Now add in all zero elements. + acc2 += (N - length) * (acc1 * acc1); + acc3 += (N - length) * acc1; + + const eT norm_val = (norm_type == 0) ? eT(N - 1) : eT(N); + const eT var_val = (acc2 - (acc3 * acc3) / eT(N)) / norm_val; + + return var_val; + } + else if(length == 1 && N > 1) // if N == 1, then variance is zero. + { + const eT mean = X[0] / eT(N); + const eT val = mean - X[0]; + + const eT acc2 = (val * val) + (N - length) * (mean * mean); + const eT acc3 = val + (N - length) * mean; + + const eT norm_val = (norm_type == 0) ? eT(N - 1) : eT(N); + const eT var_val = (acc2 - (acc3 * acc3) / eT(N)) / norm_val; + + return var_val; + } + else + { + return eT(0); + } + } + + + +template<typename T> +inline +T +spop_var::direct_var + ( + const std::complex<T>* const X, + const uword length, + const uword N, + const uword norm_type + ) + { + arma_extra_debug_sigprint(); + + typedef typename std::complex<T> eT; + + if(length >= 2 && N >= 2) + { + const eT acc1 = spop_mean::direct_mean(X, length, N); + + T acc2 = T(0); + eT acc3 = eT(0); + + for(uword i = 0; i < length; ++i) + { + const eT tmp = acc1 - X[i]; + + acc2 += std::norm(tmp); + acc3 += tmp; + } + + // Add zero elements to sums + acc2 += std::norm(acc1) * T(N - length); + acc3 += acc1 * T(N - length); + + const T norm_val = (norm_type == 0) ? T(N - 1) : T(N); + const T var_val = (acc2 - std::norm(acc3) / T(N)) / norm_val; + + return var_val; + } + else if(length == 1 && N > 1) // if N == 1, then variance is zero. + { + const eT mean = X[0] / T(N); + const eT val = mean - X[0]; + + const T acc2 = std::norm(val) + (N - length) * std::norm(mean); + const eT acc3 = val + T(N - length) * mean; + + const T norm_val = (norm_type == 0) ? T(N - 1) : T(N); + const T var_val = (acc2 - std::norm(acc3) / T(N)) / norm_val; + + return var_val; + } + else + { + return T(0); // All elements are zero + } + } + + + +template<typename T1, typename eT> +inline +eT +spop_var::iterator_var + ( + T1& it, + const T1& end, + const uword n_zero, + const uword norm_type, + const eT junk1, + const typename arma_not_cx<eT>::result* junk2 + ) + { + arma_extra_debug_sigprint(); + arma_ignore(junk1); + arma_ignore(junk2); + + T1 new_it(it); // for mean + // T1 backup_it(it); // in case we have to call robust iterator_var + eT mean = spop_mean::iterator_mean(new_it, end, n_zero, eT(0)); + + eT acc2 = eT(0); + eT acc3 = eT(0); + + const uword it_begin_pos = it.pos(); + + while(it != end) + { + const eT tmp = mean - (*it); + + acc2 += (tmp * tmp); + acc3 += (tmp); + + ++it; + } + + const uword n_nonzero = (it.pos() - it_begin_pos); + if(n_nonzero == 0) + { + return eT(0); + } + + if(n_nonzero + n_zero == 1) + { + return eT(0); // only one element + } + + // Add in entries for zeros. + acc2 += eT(n_zero) * (mean * mean); + acc3 += eT(n_zero) * mean; + + const eT norm_val = (norm_type == 0) ? eT(n_zero + n_nonzero - 1) : eT(n_zero + n_nonzero); + const eT var_val = (acc2 - (acc3 * acc3) / eT(n_nonzero + n_zero)) / norm_val; + + return var_val; + } + + + +template<typename T1, typename eT> +inline +typename get_pod_type<eT>::result +spop_var::iterator_var + ( + T1& it, + const T1& end, + const uword n_zero, + const uword norm_type, + const eT junk1, + const typename arma_cx_only<eT>::result* junk2 + ) + { + arma_extra_debug_sigprint(); + arma_ignore(junk1); + arma_ignore(junk2); + + typedef typename get_pod_type<eT>::result T; + + T1 new_it(it); // for mean + // T1 backup_it(it); // in case we have to call robust iterator_var + eT mean = spop_mean::iterator_mean(new_it, end, n_zero, eT(0)); + + T acc2 = T(0); + eT acc3 = eT(0); + + const uword it_begin_pos = it.pos(); + + while(it != end) + { + eT tmp = mean - (*it); + + acc2 += std::norm(tmp); + acc3 += (tmp); + + ++it; + } + + const uword n_nonzero = (it.pos() - it_begin_pos); + if(n_nonzero == 0) + { + return T(0); + } + + if(n_nonzero + n_zero == 1) + { + return T(0); // only one element + } + + // Add in entries for zero elements. + acc2 += T(n_zero) * std::norm(mean); + acc3 += T(n_zero) * mean; + + const T norm_val = (norm_type == 0) ? T(n_zero + n_nonzero - 1) : T(n_zero + n_nonzero); + const T var_val = (acc2 - std::norm(acc3) / T(n_nonzero + n_zero)) / norm_val; + + return var_val; + } + + + +//! @} |