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/* |
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* Copyright (c) 2005 The University of Notre Dame. All Rights Reserved. |
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* |
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* The University of Notre Dame grants you ("Licensee") a |
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* non-exclusive, royalty free, license to use, modify and |
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* redistribute this software in source and binary code form, provided |
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* that the following conditions are met: |
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* |
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* 1. Redistributions of source code must retain the above copyright |
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* notice, this list of conditions and the following disclaimer. |
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* |
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* 2. Redistributions in binary form must reproduce the above copyright |
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* notice, this list of conditions and the following disclaimer in the |
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* documentation and/or other materials provided with the |
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* distribution. |
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* |
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* This software is provided "AS IS," without a warranty of any |
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* kind. All express or implied conditions, representations and |
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* warranties, including any implied warranty of merchantability, |
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* fitness for a particular purpose or non-infringement, are hereby |
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* excluded. The University of Notre Dame and its licensors shall not |
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* be liable for any damages suffered by licensee as a result of |
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* using, modifying or distributing the software or its |
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* derivatives. In no event will the University of Notre Dame or its |
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* licensors be liable for any lost revenue, profit or data, or for |
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* direct, indirect, special, consequential, incidental or punitive |
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* damages, however caused and regardless of the theory of liability, |
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* arising out of the use of or inability to use software, even if the |
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* University of Notre Dame has been advised of the possibility of |
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* such damages. |
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* |
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* SUPPORT OPEN SCIENCE! If you use OpenMD or its source code in your |
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* research, please cite the appropriate papers when you publish your |
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* work. Good starting points are: |
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* |
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* [1] Meineke, et al., J. Comp. Chem. 26, 252-271 (2005). |
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* [2] Fennell & Gezelter, J. Chem. Phys. 124, 234104 (2006). |
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* [3] Sun, Lin & Gezelter, J. Chem. Phys. 128, 24107 (2008). |
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* [4] Vardeman & Gezelter, in progress (2009). |
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*/ |
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|
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#include <cmath> |
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|
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#include "nonbonded/SwitchingFunction.hpp" |
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#include "utils/simError.h" |
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|
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using namespace std; |
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namespace OpenMD { |
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|
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SwitchingFunction::SwitchingFunction() : np_(150), haveSpline_(false), |
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isCubic_(true), functionType_(cubic) {} |
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|
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void SwitchingFunction::setSwitchType(SwitchingFunctionType sft) { |
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if ((sft == fifth_order_poly) || (sft == cubic)) { |
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if (haveSpline_) { |
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delete switchSpline_; |
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setSwitch(rin_, rout_); |
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} |
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} else { |
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sprintf( painCave.errMsg, |
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"SwitchingFunction::setSwitchType was given unknown function type\n"); |
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painCave.severity = OPENMD_ERROR; |
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painCave.isFatal = 1; |
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simError(); |
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} |
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} |
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|
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void SwitchingFunction::setSwitch(RealType rinner, RealType router) { |
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if (router < rinner) { |
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sprintf( painCave.errMsg, |
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"SwitchingFunction::setSwitch was given rinner (%lf) which was\n" |
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"\tlarger than router (%lf).\n", rinner, router); |
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painCave.severity = OPENMD_ERROR; |
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painCave.isFatal = 1; |
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simError(); |
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} |
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if (router < 0.0) { |
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sprintf( painCave.errMsg, |
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"SwitchingFunction::setSwitch was given router (%lf) which was\n" |
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"\tless than zero.\n", router); |
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painCave.severity = OPENMD_ERROR; |
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painCave.isFatal = 1; |
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simError(); |
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} |
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if (rinner < 0.0) { |
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sprintf( painCave.errMsg, |
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"SwitchingFunction::setSwitch was given rinner (%lf) which was\n" |
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"\tless than zero.\n", router); |
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painCave.severity = OPENMD_ERROR; |
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painCave.isFatal = 1; |
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simError(); |
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} |
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|
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rin_ = rinner; |
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rout_ = router; |
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rin2_ = rin_ * rin_; |
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rout2_ = rout_ * rout_; |
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|
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if ((router - rinner) < 1.0e-8) { |
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// no reason to set up spline if the switching region is tiny |
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return; |
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} |
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|
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// setup r -> sw lookup spline |
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CubicSpline* switchSpline_ = new CubicSpline(); |
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if (functionType_ == fifth_order_poly) { |
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isCubic_ = false; |
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RealType c0 = 1.0; |
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RealType c3 = -10.0; |
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RealType c4 = 15.0; |
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RealType c5 = -6.0; |
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|
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RealType dx, r, yval, rval, rval2, rval3, rval4, rval5; |
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RealType rvaldi, rvaldi2, rvaldi3, rvaldi4, rvaldi5; |
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|
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dx = (rout_ - rin_) / RealType(np_-1); |
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|
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for (int i = 0; i < np_; i++) { |
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r = rin_ + RealType(i)*dx; |
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rval = ( r - rin_ ); |
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rval2 = rval*rval; |
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rval3 = rval2*rval; |
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rval4 = rval2*rval2; |
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rval5 = rval3*rval2; |
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rvaldi = 1.0 / ( rout_ - rin_ ); |
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rvaldi2 = rvaldi*rvaldi; |
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rvaldi3 = rvaldi2*rvaldi; |
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rvaldi4 = rvaldi2*rvaldi2; |
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rvaldi5 = rvaldi3*rvaldi2; |
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yval= c0 + c3*rval3*rvaldi3 + c4*rval4*rvaldi4 + c5*rval5*rvaldi5; |
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switchSpline_->addPoint(r, yval); |
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} |
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} else { |
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// cubic splines only need 2 points to do a cubic switching function... |
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isCubic_ = true; |
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switchSpline_->addPoint(rin_, 1.0); |
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switchSpline_->addPoint(rout_, 0.0); |
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} |
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haveSpline_ = true; |
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return; |
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} |
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|
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bool SwitchingFunction::getSwitch(RealType r2, RealType sw, RealType dswdr, |
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RealType r) { |
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sw = 1.0; |
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dswdr = 0.0; |
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bool in_switching_region = false; |
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|
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if (r2 > rin2_) { |
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if (r2 > rout2_) { |
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sw = 0.0; |
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dswdr = 0.0; |
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return in_switching_region; |
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} else { |
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in_switching_region = true; |
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r = sqrt(r2); |
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pair<RealType, RealType> result = switchSpline_->getValueAndDerivativeAt(r); |
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sw = result.first; |
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dswdr = result.second; |
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return in_switching_region; |
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} |
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} else { |
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return in_switching_region; |
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} |
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} |
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} |
