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valarray::operator[]

Returns a reference to an element or its value at specified index or a specified subset.

Type& operator[](
   size_t _Off
);
slice_array<Type> operator[](
   slice _Slicearray
);
gslice_array<Type> operator[](
   const gslice& _Gslicearray
);
mask_array<Type> operator[](
   const valarray<bool>& _Boolarray
);
indirect_array<Type> operator[](
   const valarray<size_t>& _Indarray
);
Type operator[](
   size_t _Off
) const;
valarray<Type> operator[](
     slice _Slice 
) const;
valarray<Type> operator[](
   const gslice& _Gslicearray
) const;
valarray<Type> operator[](
   const valarray<bool>& _Boolarray
) const;
valarray<Type> operator[](
   const valarray<size_t>& _Indarray
) const;

Parameters

  • _Off
    The index of the element to be assigned a value.

  • _Slicearray
    A slice_array of a valarray that specifies a subset to be selected or returned to a new valarray.

  • _Gslicearray
    A gslice_array of a valarray that specifies a subset to be selected or returned to a new valarray.

  • _Boolarray
    A bool_array of a valarray that specifies a subset to be selected or returned to a new valarray.

  • _Indarray
    An indirect_array of a valarray that specifies a subset to be selected or returned to a new valarray.

Return Value

A reference to an element or its value at specified index or a specified subset.

Remarks

The member operator is overloaded to provide several ways to select sequences of elements from among those controlled by ***this. The first group of five member operators work in conjunction with various overloads of operator= (and other assigning operators) to allow selective replacement (slicing) of the controlled sequence. The selected elements must exist.

When compiling with _SECURE_SCL 1, a runtime error will occur if you attempt to access an element outside the bounds of the valarray. See Checked Iterators for more information.

Example

See the examples for slice::slice and gslice::gslice for an example of how to declare and use the operator.

Requirements

Header: <valarray>

Namespace: std

See Also

Concepts

valarray Class

valarray Members