valarray.cc

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_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