Function Sign

cpp/src/arrow/util/basic_decimal.h:227–227

\brief Return 1 if positive or 0, -1 if strictly negative

  /// \brief Return 1 if positive or 0, -1 if strictly negative
  int64_t Sign() const { return 1 | (value_ >> (kBitWidth - 1)); }

  bool IsNegative() const { return value_ < 0; }