21 return "RandGaussZiggurat";
26 const double rzm1 = 2147483648.0, rzm2 = 4294967296.;
27 double dn=3.442619855899,tn=dn,vn=9.91256303526217e-3, q;
28 double de=7.697117470131487, te=de, ve=3.949659822581572e-3;
33 kn[0]=(
unsigned long)((dn/q)*rzm1);
40 fn[127]=exp(-.5*dn*dn);
43 dn=sqrt(-2.*log(vn/dn+exp(-.5*dn*dn)));
44 kn[i+1]=(
unsigned long)((dn/tn)*rzm1);
52 ke[0]=(
unsigned long)((de/q)*rzm2);
62 de=-log(ve/de+exp(-de));
63 ke[i+1]= (
unsigned long)((de/te)*rzm2);
77 const float r = 3.442620f;
79 unsigned long iz=hz&127;
90 return (hz>0)? r+x : -r-x;
98 if((
unsigned long)abs(hz)<
kn[iz])
return (hz*
wn[iz]);
112 for (
int i=0; i<size; ++i) {
113 vect[i] =
shoot(mean,stdDev);
119 for (
int i=0; i<size; ++i) {
120 vect[i] =
shoot(mean,stdDev);
126 for (
int i=0; i<size; ++i) {
127 vect[i] =
shoot(anEngine,mean,stdDev);
133 for (
int i=0; i<size; ++i) {
134 vect[i] =
shoot(anEngine,mean,stdDev);
140 for (
int i=0; i<size; ++i) {
147 for (
int i=0; i<size; ++i) {
154 for (
int i=0; i<size; ++i) {
155 vect[i] =
fire( mean, stdDev );
161 for (
int i=0; i<size; ++i) {
162 vect[i] =
fire( mean, stdDev );
167 int pr=os.precision(20);
168 os <<
" " <<
name() <<
"\n";
177 if (inName !=
name()) {
178 is.clear(std::ios::badbit | is.rdstate());
179 std::cerr <<
"Mismatch when expecting to read state of a "
180 <<
name() <<
" distribution\n"
181 <<
"Name found was " << inName
182 <<
"\nistream is left in the badbit state\n";
static void shootArray(const int size, float *vect, float mean=0.0, float stdDev=1.0)
std::istream & get(std::istream &is)
static bool ziggurat_init()
void fireArray(const int size, float *vect)
static float ziggurat_nfix(long hz, HepRandomEngine *anEngine)
static float ziggurat_UNI(HepRandomEngine *anEngine)
std::ostream & put(std::ostream &os) const
static float ziggurat_RNOR(HepRandomEngine *anEngine)
static unsigned long ke[256]
virtual double operator()()
static unsigned long kn[128]
static bool ziggurat_is_init
HepRandomEngine & engine()
virtual ~RandGaussZiggurat()
static unsigned long ziggurat_SHR3(HepRandomEngine *anEngine)
std::istream & get(std::istream &is)
std::ostream & put(std::ostream &os) const
shared_ptr< HepRandomEngine > localEngine
HepRandomEngine & engine()