本文整理汇总了C++中erf函数的典型用法代码示例。如果您正苦于以下问题：C++ erf函数的具体用法？C++ erf怎么用？C++ erf使用的例子？那么恭喜您, 这里精选的函数代码示例或许可以为您提供帮助。
在下文中一共展示了erf函数的15个代码示例，这些例子默认根据受欢迎程度排序。您可以为喜欢或者感觉有用的代码点赞，您的评价将有助于系统推荐出更棒的C++代码示例。
示例1: simult_chi_huber
double
vpRobust::simultscale(vpColVector &x)
{
unsigned int p = 6; //Number of parameters to be estimated.
unsigned int n = x.getRows();
double sigma2=0;
/* long */ double Expectation=0;
/* long */ double Sum_chi=0;
/* long */ double chiTmp =0;
for(unsigned int i=0; i<n; i++)
{
chiTmp = simult_chi_huber(x[i]);
Expectation += chiTmp*(1-erf(chiTmp));
Sum_chi += chiTmp;
#ifdef VP_DEBUG
#if VP_DEBUG_MODE == 3
{
std::cout << "erf = " << 1-erf(chiTmp) << std::endl;
std::cout << "x[i] = " << x[i] <<std::endl;
std::cout << "chi = " << chiTmp << std::endl;
std::cout << "Sum chi = " << chiTmp*vpMath::sqr(sig_prev) << std::endl;
std::cout << "Expectation = " << chiTmp*(1-erf(chiTmp)) << std::endl;
//getchar();
}
#endif
#endif
}
sigma2 = Sum_chi*vpMath::sqr(sig_prev)/((n-p)*Expectation);
#ifdef VP_DEBUG
#if VP_DEBUG_MODE == 3
{
std::cout << "Expectation = " << Expectation << std::endl;
std::cout << "Sum chi = " << Sum_chi << std::endl;
std::cout << "sig_prev" << sig_prev << std::endl;
std::cout << "sig_out" << sqrt(fabs(sigma2)) << std::endl;
}
#endif
#endif
return sqrt(fabs(sigma2));
}示例2: erf
Foam::scalar Foam::distributionModels::normal::sample() const
{
scalar a = erf((minValue_ - expectation_)/variance_);
scalar b = erf((maxValue_ - expectation_)/variance_);
scalar y = rndGen_.sample01<scalar>();
scalar x = erfInv(y*(b - a) + a)*variance_ + expectation_;
// Note: numerical approximation of the inverse function yields slight
// inaccuracies
x = min(max(x, minValue_), maxValue_);
return x;
}示例3: erf
Foam::scalar Foam::pdfs::lognormal::sample() const
{
scalar a = erf((minValue_ - expectation_)/variance_);
scalar b = erf((maxValue_ - expectation_)/variance_);
scalar y = rndGen_.scalar01();
scalar x = erfInv(y*(b - a) + a)*variance_ + expectation_;
// Note: numerical approximation of the inverse function yields slight
// inaccuracies
x = min(max(exp(x), exp(minValue_)), exp(maxValue_));
return log(x);
}示例4: trans_unif
static double trans_unif(double x , const arg_pack_type * arg) {
double y;
double min = arg_pack_iget_double(arg , 0);
double max = arg_pack_iget_double(arg , 1);
y = 0.5*(1 + erf(x/sqrt(2.0))); /* 0 - 1 */
return y * (max - min) + min;
}示例5: function
double function(const double phi, double **data)
{
double alfa = (*data[2]);
double tau = (*data[3]);
double X = erf((tau * phi - alfa) / sqrt((1 - tau) * (1 + tau)));
return X * X * exp(- phi * phi / 2); // / (*data[4]);
}示例6: erf
double
Partitioner::CodeCriteria::get_vote(const RegionStats *stats, std::vector<double> *votes) const
{
if (votes!=NULL)
votes->resize(dictionary.size(), NAN);
double sum=0.0, total_wt=0.0;
for (size_t cc_id=0; cc_id<criteria.size(); ++cc_id) {
if (criteria[cc_id].weight <= 0.0)
continue;
size_t stat_id = stats->find_analysis(get_name(cc_id));
if (-1==(ssize_t)stat_id)
continue;
double stat_val = stats->get_value(stat_id);
if (!std::isnan(stat_val)) {
double c = 0.0==criteria[cc_id].variance ?
(stat_val==criteria[cc_id].mean ? 1.0 : 0.0) :
1 + erf(-fabs(stat_val-criteria[cc_id].mean) / sqrt(2*criteria[cc_id].variance));
if (votes)
(*votes)[cc_id] = c;
if (!std::isnan(c)) {
sum += c * criteria[cc_id].weight;
total_wt += criteria[cc_id].weight;
}
}
}
return total_wt>0.0 ? sum / total_wt : NAN;
}示例7: sqrt
//! inverse error function is taken from NIST
double userFunctions::erfinv (double x)
{
if (x < -1 || x > 1)
return NAN;
if (x == 0)
return 0;
int sign_x;
if (x > 0) {
sign_x = 1;
} else {
sign_x = -1;
x = -x;
}
double r;
if (x <= 0.686) {
double x2 = x * x;
r = x * (((-0.140543331 * x2 + 0.914624893) * x2 + -1.645349621) * x2 + 0.886226899);
r /= (((0.012229801 * x2 + -0.329097515) * x2 + 1.442710462) * x2 + -2.118377725) * x2 + 1;
} else {
double y = sqrt (-log((1 - x) / 2));
r = (((1.641345311 * y + 3.429567803) * y + -1.62490649) * y + -1.970840454);
r /= ((1.637067800 * y + 3.543889200) * y + 1);
}
r *= sign_x;
x *= sign_x;
r -= (erf(r) - x) / (2 / sqrt (M_PI) * exp(-r*r));
return r;
}示例8: ndtr
double ndtr(double a)
{
double x, y, z;
if (isnan(a)) {
mtherr("ndtr", DOMAIN);
return (NAN);
}
x = a * SQRTH;
z = fabs(x);
if( z < SQRTH )
y = 0.5 + 0.5 * erf(x);
else
{
y = 0.5 * erfc(z);
if( x > 0 )
y = 1.0 - y;
}
return(y);
}示例9: l_erf
static double
l_erf(char *nm)
{
extern double erf();
return(erf(argument(1)));
}示例10: Phi
/*c.d.f of Standard Normal*/
double Phi(double x)
{
double tmp=x/sqrt(2.);
tmp=1+erf(tmp);
return tmp/2;
}示例11: cephes_normal
double
cephes_normal(double x)
{
double arg, result, sqrt2=1.414213562373095048801688724209698078569672;
if (x > 0) {
arg = x/sqrt2;
result = 0.5 * ( 1 + erf(arg) );
}
else {
arg = -x/sqrt2;
result = 0.5 * ( 1 - erf(arg) );
}
return( result);
}示例12: WarningIn
void Foam::equationReader::evalDimsErfDimCheck
(
const equationReader * eqnReader,
const label index,
const label i,
const label storageOffset,
label& storeIndex,
dimensionSet& xDims,
dimensionSet sourceDims
) const
{
if
(
!xDims.dimensionless() && dimensionSet::debug
)
{
WarningIn("equationReader::evalDimsErfDimCheck")
<< "Dimension error thrown for operation ["
<< equationOperation::opName
(
operator[](index)[i].operation()
)
<< "] in equation " << operator[](index).name()
<< ", given by:" << token::NL << token::TAB
<< operator[](index).rawText();
}
dimensionedScalar ds("temp", xDims, 0.0);
xDims.reset(erf(ds).dimensions());
operator[](index)[i].assignOpDimsFunction
(
&Foam::equationReader::evalDimsErf
);
}开发者ID:Unofficial-Extend-Project-Mirror，项目名称:openfoam-extend-Breeder1.6-libraries-equationReaderExtension，代码行数:33，代码来源:equationReaderEvalDimsP.C
示例13: evalf
ex evalf( const ex& x )
{
if( is_a<numeric>(x) )
return bealab::erf( ex_to<numeric>(x).to_double() );
else
return erf(x).hold();
}示例14: ATF_TC_BODY
ATF_TC_BODY(erf_inf_pos, tc)
{
const double x = 1.0L / 0.0L;
if (erf(x) != 1.0)
atf_tc_fail_nonfatal("erf(+Inf) != 1.0");
}示例15: BoysFunction
/* ************************************************************************** */
solreal BoysFunction(const int m,solreal x)
{
static const solreal srpo2=0.88622692545275801365e0; //$\sqrt{\pi}/2$
solreal srx=sqrt(x);
solreal F0=srpo2*erf(srx)/srx;
if (m==0) {return F0;}
solreal emx=exp(-x);
solreal oo2x=0.5e0/x;
if (m==1) {return ((F0-emx)*oo2x);}
solreal oo2x2=oo2x*oo2x;
if (m==2) {return (3.0e0*F0*oo2x2-emx*(oo2x+3.0e0*oo2x2));}
solreal oo2x3=oo2x*oo2x2;
if (m==3) {return (15.0e0*F0*oo2x3-emx*(oo2x+5.0e0*oo2x2+15.0e0*oo2x3));}
solreal oo2x4=oo2x2*oo2x2;
//std::cout << "oo2x4: " << oo2x4 << std::endl;
if (m==4) {return (105.0e0*F0*oo2x4-emx*(oo2x+7.0e0*oo2x2+35.0e0*oo2x3+105.0e0*oo2x4));}
solreal oo2x5=oo2x3*oo2x2;
//std::cout << "oo2x5: " << oo2x5 << std::endl;
if (m==5) {
return (945.0e0*F0*oo2x5-emx*(oo2x+9.0e0*oo2x2+63.0e0*oo2x3+315.0e0*oo2x4+945.0e0*oo2x5));
}
solreal oo2x6=oo2x3*oo2x3;
//std::cout << "oo2x6: " << oo2x6 << std::endl;
if (m==6) {
return (10395.0e0*F0*oo2x6-emx*(oo2x+11.0e0*oo2x2+99.0e0*oo2x3+693.0e0*oo2x4
+3465.0e0*oo2x5+10395.0e0*oo2x6));
}
#if DEBUG
std::cout << "This value of m (" << m << ") is not implemented yet..." << std::endl;
#endif
return 0.0e0;
}