include/valarray.cc

/***************************************************************************
 *
 * valaray.cc - Declarations for the Standard Library valarray
 *
 * $Id$
 *
 ***************************************************************************
 *
 * Licensed to the Apache Software  Foundation (ASF) under one or more
 * contributor  license agreements.  See  the NOTICE  file distributed
 * with  this  work  for  additional information  regarding  copyright
 * ownership.   The ASF  licenses this  file to  you 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.
 *
 * Copyright 1994-2008 Rogue Wave Software, Inc.
 * 
 **************************************************************************/


_RWSTD_NAMESPACE (std) { 


template <class _TypeT>
valarray<_TypeT> valarray<_TypeT>::shift (int __n) const
{
    if (0 == __n)
        return *this;

    const _RWSTD_SIZE_T __size = size ();

    if (__size <= (_RWSTD_SIZE_T)(__n < 0 ? -__n : __n))
        return valarray (__size);
        
    // use copy- rather than direct-initialization to work around
    // a gcc 3.2 bug
    _RW::__rw_array<_TypeT> __tmp =
        _RW::__rw_array<_TypeT>(_TypeT (), __size);

    // 26.3.2.7, p5 - negative n shifts right, positive left
    if (__n < 0)
        copy (_C_array.begin (), _C_array.end () + __n, __tmp.begin () - __n);
    else
        copy (_C_array.begin () + __n, _C_array.end (), __tmp.begin ());

    return valarray (__tmp);
} 


template <class _TypeT>
valarray<_TypeT> valarray<_TypeT>::cshift (int __n) const
{
    const _RWSTD_SIZE_T __size = size ();

    // compute non-negative modulus - the sign of (a % b) is
    // implementation-defined if either argument is negative (5.6, p4)
    _RWSTD_PTRDIFF_T __mod = __size ? __n % (_RWSTD_PTRDIFF_T)__size : 0;
    _RWSTD_SIZE_T    __rem = __mod < 0 ? -__mod : __mod;

    if (0 == __rem)
        return *this;

    // use copy- rather than direct-initialization to work around
    // a gcc 3.2 bug
    _RW::__rw_array<_TypeT> __tmp =
        _RW::__rw_array<_TypeT>(_TypeT (), __size);

    // 26.3.2.7, p7 - negative n rotates right, positive left
    rotate_copy (_C_array.begin (),
                 __n < 0 ? _C_array.end () - __rem : _C_array.begin () + __rem,
                 _C_array.end (), __tmp.begin ());

    return valarray (__tmp);
} 


}   // namespace std