summaryrefslogtreecommitdiffstats
path: root/src/armadillo/include/armadillo_bits/glue_polyfit_meat.hpp
diff options
context:
space:
mode:
Diffstat (limited to 'src/armadillo/include/armadillo_bits/glue_polyfit_meat.hpp')
-rw-r--r--src/armadillo/include/armadillo_bits/glue_polyfit_meat.hpp133
1 files changed, 133 insertions, 0 deletions
diff --git a/src/armadillo/include/armadillo_bits/glue_polyfit_meat.hpp b/src/armadillo/include/armadillo_bits/glue_polyfit_meat.hpp
new file mode 100644
index 0000000..3969c75
--- /dev/null
+++ b/src/armadillo/include/armadillo_bits/glue_polyfit_meat.hpp
@@ -0,0 +1,133 @@
+// 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 glue_polyfit
+//! @{
+
+
+
+template<typename eT>
+inline
+bool
+glue_polyfit::apply_noalias(Mat<eT>& out, const Col<eT>& X, const Col<eT>& Y, const uword N)
+ {
+ arma_extra_debug_sigprint();
+
+ // create Vandermonde matrix
+
+ Mat<eT> V(X.n_elem, N+1, arma_nozeros_indicator());
+
+ V.tail_cols(1).ones();
+
+ for(uword i=1; i <= N; ++i)
+ {
+ const uword j = N-i;
+
+ Col<eT> V_col_j (V.colptr(j ), V.n_rows, false, false);
+ Col<eT> V_col_jp1(V.colptr(j+1), V.n_rows, false, false);
+
+ V_col_j = V_col_jp1 % X;
+ }
+
+ Mat<eT> Q;
+ Mat<eT> R;
+
+ const bool status1 = auxlib::qr_econ(Q, R, V);
+
+ if(status1 == false) { return false; }
+
+ const bool status2 = auxlib::solve_trimat_fast(out, R, (Q.t() * Y), uword(0));
+
+ if(status2 == false) { return false; }
+
+ return true;
+ }
+
+
+
+template<typename T1, typename T2>
+inline
+bool
+glue_polyfit::apply_direct(Mat<typename T1::elem_type>& out, const Base<typename T1::elem_type,T1>& X_expr, const Base<typename T1::elem_type, T2>& Y_expr, const uword N)
+ {
+ arma_extra_debug_sigprint();
+
+ typedef typename T1::elem_type eT;
+
+ const quasi_unwrap<T1> UX(X_expr.get_ref());
+ const quasi_unwrap<T2> UY(Y_expr.get_ref());
+
+ const Mat<eT>& X = UX.M;
+ const Mat<eT>& Y = UY.M;
+
+ arma_debug_check
+ (
+ ( ((X.is_vec() == false) && (X.is_empty() == false)) || ((Y.is_vec() == false) && (Y.is_empty() == false)) ),
+ "polyfit(): given object must be a vector"
+ );
+
+ arma_debug_check( (X.n_elem != Y.n_elem), "polyfit(): given vectors must have the same number of elements" );
+
+ if(X.n_elem == 0)
+ {
+ out.reset();
+ return true;
+ }
+
+ arma_debug_check( (N >= X.n_elem), "polyfit(): N must be less than the number of elements in X" );
+
+ const Col<eT> X_as_colvec( const_cast<eT*>(X.memptr()), X.n_elem, false, false);
+ const Col<eT> Y_as_colvec( const_cast<eT*>(Y.memptr()), Y.n_elem, false, false);
+
+ bool status = false;
+
+ if(UX.is_alias(out) || UY.is_alias(out))
+ {
+ Mat<eT> tmp;
+ status = glue_polyfit::apply_noalias(tmp, X_as_colvec, Y_as_colvec, N);
+ out.steal_mem(tmp);
+ }
+ else
+ {
+ status = glue_polyfit::apply_noalias(out, X_as_colvec, Y_as_colvec, N);
+ }
+
+ return status;
+ }
+
+
+
+template<typename T1, typename T2>
+inline
+void
+glue_polyfit::apply(Mat<typename T1::elem_type>& out, const Glue<T1,T2,glue_polyfit>& expr)
+ {
+ arma_extra_debug_sigprint();
+
+ const bool status = glue_polyfit::apply_direct(out, expr.A, expr.B, expr.aux_uword);
+
+ if(status == false)
+ {
+ out.soft_reset();
+ arma_stop_runtime_error("polyfit(): failed");
+ }
+ }
+
+
+
+//! @}