ArrayNDScanner.h

Go to the documentation of this file.

#ifndef NPSTAT_ARRAYNDSCANNER_HH_
#define NPSTAT_ARRAYNDSCANNER_HH_

#include <vector>
#include <climits>

namespace npstat {
  class ArrayNDScanner {
  public:

    inline ArrayNDScanner(const unsigned* shape, const unsigned lenShape) { initialize(shape, lenShape); }

    inline explicit ArrayNDScanner(const std::vector<unsigned>& shape) {
      initialize(shape.empty() ? static_cast<unsigned*>(nullptr) : &shape[0], shape.size());
    }

    ArrayNDScanner() = delete;

    inline unsigned dim() const { return dim_; }

    inline unsigned long state() const { return state_; }

    inline unsigned long maxState() const { return maxState_; }

    inline bool isValid() const { return state_ < maxState_; }

    void getIndex(unsigned* index, unsigned indexBufferLen) const;

    inline void reset() { state_ = 0UL; }

    inline ArrayNDScanner& operator++() {
      if (state_ < maxState_)
        ++state_;
      return *this;
    }

    inline void operator++(int) {
      if (state_ < maxState_)
        ++state_;
    }

    inline void setState(const unsigned long state) { state_ = state <= maxState_ ? state : maxState_; }

  private:
    void initialize(const unsigned* shape, unsigned lenShape);

    unsigned long strides_[CHAR_BIT * sizeof(unsigned long)];
    unsigned long state_;
    unsigned long maxState_;
    unsigned dim_;
  };
}  // namespace npstat

#endif  // NPSTAT_ARRAYSCANNER_HH_