Chris@49: // Copyright (C) 2008-2012 NICTA (www.nicta.com.au)
Chris@49: // Copyright (C) 2008-2012 Conrad Sanderson
Chris@49: // Copyright (C) 2012 Ryan Curtin
Chris@49: // 
Chris@49: // This Source Code Form is subject to the terms of the Mozilla Public
Chris@49: // License, v. 2.0. If a copy of the MPL was not distributed with this
Chris@49: // file, You can obtain one at http://mozilla.org/MPL/2.0/.
Chris@49: 
Chris@49: 
Chris@49: //! \addtogroup operator_minus
Chris@49: //! @{
Chris@49: 
Chris@49: 
Chris@49: 
Chris@49: //! unary -
Chris@49: template<typename T1>
Chris@49: arma_inline
Chris@49: typename
Chris@49: enable_if2< is_arma_type<T1>::value, const eOp<T1, eop_neg> >::result
Chris@49: operator-
Chris@49: (const T1& X)
Chris@49:   {
Chris@49:   arma_extra_debug_sigprint();
Chris@49:   
Chris@49:   return eOp<T1,eop_neg>(X);
Chris@49:   }
Chris@49: 
Chris@49: 
Chris@49: 
Chris@49: //! cancellation of two consecutive negations: -(-T1)
Chris@49: template<typename T1>
Chris@49: arma_inline
Chris@49: const T1&
Chris@49: operator-
Chris@49: (const eOp<T1, eop_neg>& X)
Chris@49:   {
Chris@49:   arma_extra_debug_sigprint();
Chris@49:   
Chris@49:   return X.m;
Chris@49:   }
Chris@49: 
Chris@49: 
Chris@49: 
Chris@49: //! Base - scalar
Chris@49: template<typename T1>
Chris@49: arma_inline
Chris@49: typename
Chris@49: enable_if2< is_arma_type<T1>::value, const eOp<T1, eop_scalar_minus_post> >::result
Chris@49: operator-
Chris@49:   (
Chris@49:   const T1&                    X,
Chris@49:   const typename T1::elem_type k
Chris@49:   )
Chris@49:   {
Chris@49:   arma_extra_debug_sigprint();
Chris@49:   
Chris@49:   return eOp<T1, eop_scalar_minus_post>(X, k);
Chris@49:   }
Chris@49: 
Chris@49: 
Chris@49: 
Chris@49: //! scalar - Base
Chris@49: template<typename T1>
Chris@49: arma_inline
Chris@49: typename
Chris@49: enable_if2< is_arma_type<T1>::value, const eOp<T1, eop_scalar_minus_pre> >::result
Chris@49: operator-
Chris@49:   (
Chris@49:   const typename T1::elem_type k,
Chris@49:   const T1&                    X
Chris@49:   )
Chris@49:   {
Chris@49:   arma_extra_debug_sigprint();
Chris@49:   
Chris@49:   return eOp<T1, eop_scalar_minus_pre>(X, k);
Chris@49:   }
Chris@49: 
Chris@49: 
Chris@49: 
Chris@49: //! complex scalar - non-complex Base
Chris@49: template<typename T1>
Chris@49: arma_inline
Chris@49: typename
Chris@49: enable_if2
Chris@49:   <
Chris@49:   (is_arma_type<T1>::value && is_complex<typename T1::elem_type>::value == false),
Chris@49:   const mtOp<typename std::complex<typename T1::pod_type>, T1, op_cx_scalar_minus_pre>
Chris@49:   >::result
Chris@49: operator-
Chris@49:   (
Chris@49:   const std::complex<typename T1::pod_type>& k,
Chris@49:   const T1&                                  X
Chris@49:   )
Chris@49:   {
Chris@49:   arma_extra_debug_sigprint();
Chris@49:   
Chris@49:   return mtOp<typename std::complex<typename T1::pod_type>, T1, op_cx_scalar_minus_pre>('j', X, k);
Chris@49:   }
Chris@49: 
Chris@49: 
Chris@49: 
Chris@49: //! non-complex Base - complex scalar
Chris@49: template<typename T1>
Chris@49: arma_inline
Chris@49: typename
Chris@49: enable_if2
Chris@49:   <
Chris@49:   (is_arma_type<T1>::value && is_complex<typename T1::elem_type>::value == false),
Chris@49:   const mtOp<typename std::complex<typename T1::pod_type>, T1, op_cx_scalar_minus_post>
Chris@49:   >::result
Chris@49: operator-
Chris@49:   (
Chris@49:   const T1&                                  X,
Chris@49:   const std::complex<typename T1::pod_type>& k
Chris@49:   )
Chris@49:   {
Chris@49:   arma_extra_debug_sigprint();
Chris@49:   
Chris@49:   return mtOp<typename std::complex<typename T1::pod_type>, T1, op_cx_scalar_minus_post>('j', X, k);
Chris@49:   }
Chris@49: 
Chris@49: 
Chris@49: 
Chris@49: //! subtraction of Base objects with same element type
Chris@49: template<typename T1, typename T2>
Chris@49: arma_inline
Chris@49: typename
Chris@49: enable_if2
Chris@49:   <
Chris@49:   is_arma_type<T1>::value && is_arma_type<T2>::value && is_same_type<typename T1::elem_type, typename T2::elem_type>::value,
Chris@49:   const eGlue<T1, T2, eglue_minus>
Chris@49:   >::result
Chris@49: operator-
Chris@49:   (
Chris@49:   const T1& X,
Chris@49:   const T2& Y
Chris@49:   )
Chris@49:   {
Chris@49:   arma_extra_debug_sigprint();
Chris@49:   
Chris@49:   return eGlue<T1, T2, eglue_minus>(X, Y);
Chris@49:   }
Chris@49: 
Chris@49: 
Chris@49: 
Chris@49: //! subtraction of Base objects with different element types
Chris@49: template<typename T1, typename T2>
Chris@49: inline
Chris@49: typename
Chris@49: enable_if2
Chris@49:   <
Chris@49:   (is_arma_type<T1>::value && is_arma_type<T2>::value && (is_same_type<typename T1::elem_type, typename T2::elem_type>::value == false)),
Chris@49:   const mtGlue<typename promote_type<typename T1::elem_type, typename T2::elem_type>::result, T1, T2, glue_mixed_minus>
Chris@49:   >::result
Chris@49: operator-
Chris@49:   (
Chris@49:   const T1& X,
Chris@49:   const T2& Y
Chris@49:   )
Chris@49:   {
Chris@49:   arma_extra_debug_sigprint();
Chris@49:   
Chris@49:   typedef typename T1::elem_type eT1;
Chris@49:   typedef typename T2::elem_type eT2;
Chris@49:   
Chris@49:   typedef typename promote_type<eT1,eT2>::result out_eT;
Chris@49:   
Chris@49:   promote_type<eT1,eT2>::check();
Chris@49:   
Chris@49:   return mtGlue<out_eT, T1, T2, glue_mixed_minus>( X, Y );
Chris@49:   }
Chris@49: 
Chris@49: 
Chris@49: 
Chris@49: //! subtraction of two sparse objects
Chris@49: template<typename T1, typename T2>
Chris@49: inline
Chris@49: typename
Chris@49: enable_if2
Chris@49:   <
Chris@49:   (is_arma_sparse_type<T1>::value && is_arma_sparse_type<T2>::value && is_same_type<typename T1::elem_type, typename T2::elem_type>::value),
Chris@49:   const SpGlue<T1,T2,spglue_minus>
Chris@49:   >::result
Chris@49: operator-
Chris@49:   (
Chris@49:   const T1& X,
Chris@49:   const T2& Y
Chris@49:   )
Chris@49:   {
Chris@49:   arma_extra_debug_sigprint();
Chris@49:   
Chris@49:   return SpGlue<T1,T2,spglue_minus>(X,Y);
Chris@49:   }
Chris@49: 
Chris@49: 
Chris@49: 
Chris@49: //! subtraction of one sparse and one dense object
Chris@49: template<typename T1, typename T2>
Chris@49: inline
Chris@49: typename
Chris@49: enable_if2
Chris@49:   <
Chris@49:   (is_arma_sparse_type<T1>::value && is_arma_type<T2>::value && is_same_type<typename T1::elem_type, typename T2::elem_type>::value),
Chris@49:   Mat<typename T1::elem_type>
Chris@49:   >::result
Chris@49: operator-
Chris@49:   (
Chris@49:   const T1& x,
Chris@49:   const T2& y
Chris@49:   )
Chris@49:   {
Chris@49:   arma_extra_debug_sigprint();
Chris@49:   
Chris@49:   const SpProxy<T1> pa(x);
Chris@49:   
Chris@49:   Mat<typename T1::elem_type> result(-y);
Chris@49:   
Chris@49:   arma_debug_assert_same_size( pa.get_n_rows(), pa.get_n_cols(), result.n_rows, result.n_cols, "subtraction" );
Chris@49:   
Chris@49:   typename SpProxy<T1>::const_iterator_type it     = pa.begin();
Chris@49:   typename SpProxy<T1>::const_iterator_type it_end = pa.end();
Chris@49:   
Chris@49:   while(it != it_end)
Chris@49:     {
Chris@49:     result.at(it.row(), it.col()) += (*it);
Chris@49:     ++it;
Chris@49:     }
Chris@49:   
Chris@49:   return result;
Chris@49:   }
Chris@49: 
Chris@49: 
Chris@49: 
Chris@49: //! subtraction of one dense and one sparse object
Chris@49: template<typename T1, typename T2>
Chris@49: inline
Chris@49: typename
Chris@49: enable_if2
Chris@49:   <
Chris@49:   (is_arma_type<T1>::value && is_arma_sparse_type<T2>::value && is_same_type<typename T1::elem_type, typename T2::elem_type>::value),
Chris@49:   Mat<typename T1::elem_type>
Chris@49:   >::result
Chris@49: operator-
Chris@49:   (
Chris@49:   const T1& x,
Chris@49:   const T2& y
Chris@49:   )
Chris@49:   {
Chris@49:   arma_extra_debug_sigprint();
Chris@49:   
Chris@49:   Mat<typename T1::elem_type> result(x);
Chris@49:   
Chris@49:   const SpProxy<T2> pb(y.get_ref());
Chris@49:   
Chris@49:   arma_debug_assert_same_size( result.n_rows, result.n_cols, pb.get_n_rows(), pb.get_n_cols(), "subtraction" );
Chris@49:   
Chris@49:   typename SpProxy<T2>::const_iterator_type it     = pb.begin();
Chris@49:   typename SpProxy<T2>::const_iterator_type it_end = pb.end();
Chris@49: 
Chris@49:   while(it != it_end)
Chris@49:     {
Chris@49:     result.at(it.row(), it.col()) -= (*it);
Chris@49:     ++it;
Chris@49:     }
Chris@49:   
Chris@49:   return result;
Chris@49:   }
Chris@49: 
Chris@49: 
Chris@49: 
Chris@49: //! @}