// Ewald::FillErfcTable()
void Ewald::FillErfcTable(double cutoffIn, double dxdr) {
one_over_Dx_ = 1.0 / erfcTableDx_;
unsigned int erfcTableSize = (unsigned int)(dxdr * one_over_Dx_ * cutoffIn * 1.5);
Darray erfc_X, erfc_Y;
erfc_X.reserve( erfcTableSize );
erfc_Y.reserve( erfcTableSize );
// Save X and Y values so we can calc the spline coefficients
double xval = 0.0;
for (unsigned int i = 0; i != erfcTableSize; i++) {
double yval = erfc_func( xval );
erfc_X.push_back( xval );
erfc_Y.push_back( yval );
xval += erfcTableDx_;
}
Spline cspline;
cspline.CubicSpline_Coeff(erfc_X, erfc_Y);
erfc_X.clear();
// Store values in Spline table
erfc_table_.reserve( erfcTableSize * 4 ); // Y B C D
for (unsigned int i = 0; i != erfcTableSize; i++) {
erfc_table_.push_back( erfc_Y[i] );
erfc_table_.push_back( cspline.B_coeff()[i] );
erfc_table_.push_back( cspline.C_coeff()[i] );
erfc_table_.push_back( cspline.D_coeff()[i] );
}
// Memory saved Y values plus spline B, C, and D coefficient arrays.
mprintf("\tMemory used by Erfc table and splines: %s\n",
ByteString(erfc_table_.size() * sizeof(double), BYTE_DECIMAL).c_str());
}
