aGrUM  0.13.2
pow_inl.h
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27 // To help IDE Parsers
28 #include <agrum/core/math/pow.h>
29 
30 namespace gum {
31  //@beforeMerging is this really faster ?
32  // Specialized pow function with integers (faster implementation).
33  INLINE unsigned long intPow(unsigned long base, unsigned long exponent) {
34  if (exponent == 0) { return 1UL; }
35 
36  unsigned long out = base;
37 
38  for (unsigned long i = 1; i < exponent; i++)
39  out *= base;
40 
41  return out;
42  }
43 
44  //@beforeMerging is this really faster ?
45  // Specialized base 2 pow function with integer.
46  INLINE unsigned long int2Pow(unsigned long exponent) { return 1UL << exponent; }
47 
48  //@beforeMerging is this really faster ?
49  // Given an integer, compute it's - superior - and closest power of two, i.e.
50  // the number of bits necessary to represent this integer as well as the
51  // maximum integer that can be represented by those bits.
52  INLINE void superiorPow(unsigned long card,
53  unsigned long& num_bits,
54  unsigned long& new_card) {
55  if (card == 0) {
56  num_bits = 0;
57  new_card = 1;
58  return;
59  }
60 
61  num_bits = 1;
62  new_card = 2;
63 
64  while (new_card < card) {
65  new_card *= 2;
66  num_bits++;
67  }
68  }
69 
70 } // namespace gum
unsigned long int2Pow(unsigned long exponent)
Specialized base 2 pow function with integer.
Definition: pow_inl.h:46
Implementation of pow functions with integers, faster than stl implementation.
gum is the global namespace for all aGrUM entities
Definition: agrum.h:25
void superiorPow(unsigned long card, unsigned long &num_bits, unsigned long &new_card)
Compute the superior and closest power of two of an integer.
Definition: pow_inl.h:52
unsigned long intPow(unsigned long base, unsigned long exponent)
Specialized pow function with integers (faster implementation).
Definition: pow_inl.h:33