pow_inl.h

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// To help IDE Parsers
#include <agrum/core/math/pow.h>

namespace gum {
  //@beforeMerging is this really faster ?
  // Specialized pow function with integers (faster implementation).
  INLINE unsigned long intPow(unsigned long base, unsigned long exponent) {
    if (exponent == 0) { return 1UL; }

    unsigned long out = base;

    for (unsigned long i = 1; i < exponent; i++)
      out *= base;

    return out;
  }

  //@beforeMerging is this really faster ?
  // Specialized base 2 pow function with integer.
  INLINE unsigned long int2Pow(unsigned long exponent) { return 1UL << exponent; }

  //@beforeMerging is this really faster ?
  // Given an integer, compute it's - superior - and closest power of two, i.e.
  // the number of bits necessary to represent this integer as well as the
  // maximum integer that can be represented by those bits.
  INLINE void superiorPow(unsigned long  card,
                          unsigned long& num_bits,
                          unsigned long& new_card) {
    if (card == 0) {
      num_bits = 0;
      new_card = 1;
      return;
    }

    num_bits = 1;
    new_card = 2;

    while (new_card < card) {
      new_card *= 2;
      num_bits++;
    }
  }

}   // namespace gum