slice

class slice {
public:
    slice();
    slice(size_t st, size_t len, size_t str);
    size_t start() const;
    size_t size() const;
    size_t stride() const;
    };

The class stores the parameters that characterize a slice_array when an object of class slice appears as a subscript for an object of class valarray<T>. The stored values include:

• A starting index
• A total length
• A stride, or distance between subsequent indices