26 Numerics library [numerics]

26.7 Numeric arrays [numarray]

26.7.2 Class template valarray [template.valarray]

26.7.2.2 Constructors [valarray.cons]

valarray();

Effects: Constructs a valarray that has zero length.250

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explicit valarray(size_t n);

Effects: Constructs a valarray that has length n.

Each element of the array is value-initialized .

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valarray(const T& v, size_t n);

Effects: Constructs a valarray that has length n.

Each element of the array is initialized with v.

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valarray(const T* p, size_t n);

Preconditions: [p, p + n) is a valid range.

Effects: Constructs a valarray that has length n.

The values of the elements of the array are initialized with the first n values pointed to by the first argument.251

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valarray(const valarray& v);

Effects: Constructs a valarray that has the same length as v.

The elements are initialized with the values of the corresponding elements of v.252

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valarray(valarray&& v) noexcept;

Effects: Constructs a valarray that has the same length as v.

The elements are initialized with the values of the corresponding elements of v.

Complexity: Constant.

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valarray(initializer_list<T> il);

Effects: Equivalent to valarray(il.begin(), il.size()).

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valarray(const slice_array<T>&);
valarray(const gslice_array<T>&);
valarray(const mask_array<T>&);
valarray(const indirect_array<T>&);

These conversion constructors convert one of the four reference templates to a valarray.

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~valarray();

Effects: The destructor is applied to every element of *this; an implementation may return all allocated memory.

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This default constructor is essential, since arrays of valarray may be useful.

After initialization, the length of an empty array can be increased with the resize member function.

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This constructor is the preferred method for converting a C array to a valarray object.

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This copy constructor creates a distinct array rather than an alias.

Implementations in which arrays share storage are permitted, but they would need to implement a copy-on-reference mechanism to ensure that arrays are conceptually distinct.

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