Go to the documentation of this file.00001 #include "statsLib.h"
00002
00037 dvariable dbeta( const dvariable& x, const double& shape1, const double& shape2 )
00038 {
00039 if( x<=0 || x>=1.0 )
00040 {
00041 cerr<<"x is <=0 or >=1.0 in "
00042 "dbeta( const dvariable& x, const double& shape1, const double& shape2 )\n";
00043 return 0;
00044 }
00045
00046 if( shape1<=0 || shape2 <=0 )
00047 {
00048 cerr<<"shape1 or shape2 is <= 0 in "
00049 "dbeta( const dvariable& x, const double& shape1, const double& shape2 )\n";
00050 return 0;
00051 }
00052
00053 double a=shape1;
00054 double b=shape2;
00055 return -1.* gammln(a+b)+(gammln(a)+gammln(b))-(a-1.)*log(x)-(b-1.)*log(1.-x);
00056 }
00057
00058 dvariable dbeta( const dvariable& x, const dvariable& shape1, const dvariable& shape2 )
00059 {
00060 if( x<=0 || x>=1.0 )
00061 {
00062 cerr<<"x is <=0 or >=1.0 in "
00063 "dbeta( const dvariable& x, const double& shape1, const double& shape2 )\n";
00064 return 0;
00065 }
00066
00067 if( shape1<=0 || shape2 <=0 )
00068 {
00069 cerr<<"shape1 or shape2 is <= 0 in "
00070 "dbeta( const dvariable& x, const double& shape1, const double& shape2 )\n";
00071 return 0;
00072 }
00073
00074 dvariable a=shape1;
00075 dvariable b=shape2;
00076 return -1.* gammln(a+b)+(gammln(a)+gammln(b))-(a-1.)*log(x)-(b-1.)*log(1.-x);
00077 }
00078
00079 dvariable dbeta( const dvariable& x, const prevariable& shape1, const prevariable& shape2 )
00080 {
00081 if( x<=0 || x>=1.0 )
00082 {
00083 cerr<<"x is <=0 or >=1.0 in "
00084 "dbeta( const dvariable& x, const double& shape1, const double& shape2 )\n";
00085 return 0;
00086 }
00087
00088 if( shape1<=0 || shape2 <=0 )
00089 {
00090 cerr<<"shape1 or shape2 is <= 0 in "
00091 "dbeta( const dvariable& x, const double& shape1, const double& shape2 )\n";
00092 return 0;
00093 }
00094
00095 dvariable a=shape1;
00096 dvariable b=shape2;
00097 return -1.* gammln(a+b)+(gammln(a)+gammln(b))-(a-1.)*log(x)-(b-1.)*log(1.-x);
00098 }
00099
1.8.0
