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Differential D58 Diff 259 src/EvtGenBase/EvtCGCoefSingle.cpp

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src/EvtGenBase/EvtCGCoefSingle.cpp

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#include <assert.h> #include <assert.h>
#include <iostream> #include <iostream>
#include <math.h> #include <math.h>
#include <stdlib.h> #include <stdlib.h>
void EvtCGCoefSingle::init( int j1, int j2 ) void EvtCGCoefSingle::init( int j1, int j2 )
{ {
_j1 = j1; m_j1 = j1;
_j2 = j2; m_j2 = j2;
_Jmax = abs( j1 + j2 ); m_Jmax = abs( j1 + j2 );
_Jmin = abs( j1 - j2 ); m_Jmin = abs( j1 - j2 );
_table.resize( ( _Jmax - _Jmin ) / 2 + 1 ); m_table.resize( ( m_Jmax - m_Jmin ) / 2 + 1 );
int J, M; int J, M;
int lenmax = j1 + 1; int lenmax = j1 + 1;
if ( j2 < j1 ) if ( j2 < j1 )
lenmax = j2 + 1; lenmax = j2 + 1;
//set vector sizes //set vector sizes
for ( J = _Jmax; J >= _Jmin; J -= 2 ) { for ( J = m_Jmax; J >= m_Jmin; J -= 2 ) {
_table[( J - _Jmin ) / 2].resize( J + 1 ); m_table[( J - m_Jmin ) / 2].resize( J + 1 );
for ( M = J; J >= -M; M -= 2 ) { for ( M = J; J >= -M; M -= 2 ) {
int len = ( ( _j1 + _j2 ) - abs( M ) ) / 2 + 1; int len = ( ( m_j1 + m_j2 ) - abs( M ) ) / 2 + 1;
if ( len > lenmax ) if ( len > lenmax )
len = lenmax; len = lenmax;
_table[( J - _Jmin ) / 2][( M + J ) / 2].resize( len ); m_table[( J - m_Jmin ) / 2][( M + J ) / 2].resize( len );
} }
} }
//now fill the vectors //now fill the vectors
for ( J = _Jmax; J >= _Jmin; J -= 2 ) { for ( J = m_Jmax; J >= m_Jmin; J -= 2 ) {
//bootstrap with highest M(=J) as a special case //bootstrap with highest M(=J) as a special case
if ( J == _Jmax ) { if ( J == m_Jmax ) {
cg( J, J, _j1, _j2 ) = 1.0; cg( J, J, m_j1, m_j2 ) = 1.0;
} else { } else {
int n = ( _Jmax - J ) / 2 + 1; int n = ( m_Jmax - J ) / 2 + 1;
std::vector<double>* vectors = new std::vector<double>[n - 1]; std::vector<double>* vectors = new std::vector<double>[n - 1];
int i, k; int i, k;
for ( i = 0; i < n - 1; i++ ) { for ( i = 0; i < n - 1; i++ ) {
// i corresponds to J=Jmax-2*i // i corresponds to J=Jmax-2*i
vectors[i].resize( n ); vectors[i].resize( n );
for ( k = 0; k < n; k++ ) { for ( k = 0; k < n; k++ ) {
double tmp = _table[( _Jmax - _Jmin ) / 2 - i] double tmp = m_table[( m_Jmax - m_Jmin ) / 2 - i]
[( J + _Jmax - 2 * i ) / 2][k]; [( J + m_Jmax - 2 * i ) / 2][k];
vectors[i][k] = tmp; vectors[i][k] = tmp;
} }
} }
EvtOrthogVector getOrth( n, vectors ); EvtOrthogVector getOrth( n, vectors );
std::vector<double> orth = getOrth.getOrthogVector(); std::vector<double> orth = getOrth.getOrthogVector();
int sign = 1; int sign = 1;
if ( orth[n - 1] < 0.0 ) if ( orth[n - 1] < 0.0 )
sign = -1; sign = -1;
for ( k = 0; k < n; k++ ) { for ( k = 0; k < n; k++ ) {
_table[( J - _Jmin ) / 2][J][k] = sign * orth[k]; m_table[( J - m_Jmin ) / 2][J][k] = sign * orth[k];
} }
delete[] vectors; delete[] vectors;
} }
for ( M = J - 2; M >= -J; M -= 2 ) { for ( M = J - 2; M >= -J; M -= 2 ) {
int len = ( ( _j1 + _j2 ) - abs( M ) ) / 2 + 1; int len = ( ( m_j1 + m_j2 ) - abs( M ) ) / 2 + 1;
if ( len > lenmax ) if ( len > lenmax )
len = lenmax; len = lenmax;
int mmin = M - j2; int mmin = M - j2;
if ( mmin < -j1 ) if ( mmin < -j1 )
mmin = -j1; mmin = -j1;
int m1; int m1;
for ( m1 = mmin; m1 < mmin + len * 2; m1 += 2 ) { for ( m1 = mmin; m1 < mmin + len * 2; m1 += 2 ) {
int m2 = M - m1; int m2 = M - m1;
double sum = 0.0; double sum = 0.0;
float fkwTmp = _j1 * ( _j1 + 2 ) - ( m1 + 2 ) * m1; float fkwTmp = m_j1 * ( m_j1 + 2 ) - ( m1 + 2 ) * m1;
//fkw 2/2/2001: changes needed to satisfy KCC //fkw 2/2/2001: changes needed to satisfy KCC
//fkw if (m1+2<=_j1) sum+=0.5*sqrt(_j1*(_j1+2)-(m1+2)*m1)*cg(J,M+2,m1+2,m2); //fkw if (m1+2<=m_j1) sum+=0.5*sqrt(m_j1*(m_j1+2)-(m1+2)*m1)*cg(J,M+2,m1+2,m2);
//fkw if (m2+2<=_j2) sum+=0.5*sqrt(_j2*(_j2+2)-(m2+2)*m2)*cg(J,M+2,m1,m2+2); //fkw if (m2+2<=m_j2) sum+=0.5*sqrt(m_j2*(m_j2+2)-(m2+2)*m2)*cg(J,M+2,m1,m2+2);
//fkw sum/=(0.5*sqrt(J*(J+2)-(M+2)*M)); //fkw sum/=(0.5*sqrt(J*(J+2)-(M+2)*M));
if ( m1 + 2 <= _j1 ) if ( m1 + 2 <= m_j1 )
sum += 0.5 * sqrt( fkwTmp ) * cg( J, M + 2, m1 + 2, m2 ); sum += 0.5 * sqrt( fkwTmp ) * cg( J, M + 2, m1 + 2, m2 );
fkwTmp = _j2 * ( _j2 + 2 ) - ( m2 + 2 ) * m2; fkwTmp = m_j2 * ( m_j2 + 2 ) - ( m2 + 2 ) * m2;
if ( m2 + 2 <= _j2 ) if ( m2 + 2 <= m_j2 )
sum += 0.5 * sqrt( fkwTmp ) * cg( J, M + 2, m1, m2 + 2 ); sum += 0.5 * sqrt( fkwTmp ) * cg( J, M + 2, m1, m2 + 2 );
fkwTmp = J * ( J + 2 ) - ( M + 2 ) * M; fkwTmp = J * ( J + 2 ) - ( M + 2 ) * M;
sum /= ( 0.5 * sqrt( fkwTmp ) ); sum /= ( 0.5 * sqrt( fkwTmp ) );
cg( J, M, m1, m2 ) = sum; cg( J, M, m1, m2 ) = sum;
} }
} }
} }
} }
double EvtCGCoefSingle::coef( int J, int M, int j1, int j2, int m1, int m2 ) double EvtCGCoefSingle::coef( int J, int M, int j1, int j2, int m1, int m2 )
{ {
assert( j1 == _j1 ); assert( j1 == m_j1 );
_unused( j1 ); UNUSED( j1 );
assert( j2 == _j2 ); assert( j2 == m_j2 );
_unused( j2 ); UNUSED( j2 );
return cg( J, M, m1, m2 ); return cg( J, M, m1, m2 );
} }
double& EvtCGCoefSingle::cg( int J, int M, int m1, int m2 ) double& EvtCGCoefSingle::cg( int J, int M, int m1, int m2 )
{ {
assert( M == m1 + m2 ); assert( M == m1 + m2 );
_unused( m2 ); UNUSED( m2 );
assert( abs( M ) <= J ); assert( abs( M ) <= J );
assert( J <= _Jmax ); assert( J <= m_Jmax );
assert( J >= _Jmin ); assert( J >= m_Jmin );
assert( abs( m1 ) <= _j1 ); assert( abs( m1 ) <= m_j1 );
assert( abs( m2 ) <= _j2 ); assert( abs( m2 ) <= m_j2 );
//find lowest m1 allowed for the given M //find lowest m1 allowed for the given M
int mmin = M - _j2; int mmin = M - m_j2;
if ( mmin < -_j1 ) if ( mmin < -m_j1 )
mmin = -_j1; mmin = -m_j1;
int n = m1 - mmin; int n = m1 - mmin;
return _table[( J - _Jmin ) / 2][( M + J ) / 2][n / 2]; return m_table[( J - m_Jmin ) / 2][( M + J ) / 2][n / 2];
} }