ROOT   6.10/09 Reference Guide
TMathBase.cxx
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1 // @(#)root/base:$Id$
2 // Authors: Rene Brun 08/02/2007
3
4 /*************************************************************************
7  * *
8  * For the licensing terms see $ROOTSYS/LICENSE. * 9 * For the list of contributors see$ROOTSYS/README/CREDITS. *
10  *************************************************************************/
11
12 /** TMath Base functions
13 \ingroup Base
14
15 Define the functions Min, Max, Abs, Sign, Range for all types.
16 NB: These functions are unfortunately not available in a portable
17 way in std::.
18
19 More functions are defined in TMath.h. TMathBase.h is designed to be
20 a stable file and used in place of TMath.h in the ROOT miniCore.
21 */
22
23 #include "TMathBase.h"
24 #include <math.h>
25
26 ////////////////////////////////////////////////////////////////////////////////
27 /// Return next prime number after x, unless x is a prime in which case
28 /// x is returned.
29
31 {
32  if (x <= 2)
33  return 2;
34  if (x == 3)
35  return 3;
36
37  if (x % 2 == 0)
38  x++;
39
40  Long_t sqr = (Long_t) sqrt((Double_t)x) + 1;
41
42  for (;;) {
43  Long_t n;
44  for (n = 3; (n <= sqr) && ((x % n) != 0); n += 2)
45  ;
46  if (n > sqr)
47  return x;
48  x += 2;
49  }
50 }
double sqrt(double)
Double_t x[n]
Definition: legend1.C:17
long Long_t
Definition: RtypesCore.h:50
double Double_t
Definition: RtypesCore.h:55
Long_t NextPrime(Long_t x)
TMath Base functionsDefine the functions Min, Max, Abs, Sign, Range for all types.
Definition: TMathBase.cxx:30
VecExpr< UnaryOp< Sqr< T >, VecExpr< A, T, D >, T >, T, D > sqr(const VecExpr< A, T, D > &rhs)
const Int_t n
Definition: legend1.C:16