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Comparing:
trunk/src/math/SphericalHarmonic.cpp (file contents), Revision 1042 by gezelter, Wed Sep 20 22:16:23 2006 UTC vs.
branches/development/src/math/SphericalHarmonic.cpp (file contents), Revision 1465 by chuckv, Fri Jul 9 23:08:25 2010 UTC

# Line 6 | Line 6
6   * redistribute this software in source and binary code form, provided
7   * that the following conditions are met:
8   *
9 < * 1. Acknowledgement of the program authors must be made in any
10 < *    publication of scientific results based in part on use of the
11 < *    program.  An acceptable form of acknowledgement is citation of
12 < *    the article in which the program was described (Matthew
13 < *    A. Meineke, Charles F. Vardeman II, Teng Lin, Christopher
14 < *    J. Fennell and J. Daniel Gezelter, "OOPSE: An Object-Oriented
15 < *    Parallel Simulation Engine for Molecular Dynamics,"
16 < *    J. Comput. Chem. 26, pp. 252-271 (2005))
17 < *
18 < * 2. Redistributions of source code must retain the above copyright
9 > * 1. Redistributions of source code must retain the above copyright
10   *    notice, this list of conditions and the following disclaimer.
11   *
12 < * 3. Redistributions in binary form must reproduce the above copyright
12 > * 2. Redistributions in binary form must reproduce the above copyright
13   *    notice, this list of conditions and the following disclaimer in the
14   *    documentation and/or other materials provided with the
15   *    distribution.
# Line 37 | Line 28
28   * arising out of the use of or inability to use software, even if the
29   * University of Notre Dame has been advised of the possibility of
30   * such damages.
31 + *
32 + * SUPPORT OPEN SCIENCE!  If you use OpenMD or its source code in your
33 + * research, please cite the appropriate papers when you publish your
34 + * work.  Good starting points are:
35 + *                                                                      
36 + * [1]  Meineke, et al., J. Comp. Chem. 26, 252-271 (2005).            
37 + * [2]  Fennell & Gezelter, J. Chem. Phys. 124, 234104 (2006).          
38 + * [3]  Sun, Lin & Gezelter, J. Chem. Phys. 128, 24107 (2008).          
39 + * [4]  Vardeman & Gezelter, in progress (2009).                        
40   */
41  
42   #include <stdio.h>
43 + #include <cmath>
44   #include <limits>
45   #include "math/SphericalHarmonic.hpp"
46   #include "utils/simError.h"
47  
48 < using namespace oopse;
48 > using namespace OpenMD;
49  
50   SphericalHarmonic::SphericalHarmonic() {
51   }
# Line 52 | Line 53 | ComplexType SphericalHarmonic::getValueAt(RealType cos
53   ComplexType SphericalHarmonic::getValueAt(RealType costheta, RealType phi) {
54    
55    RealType p;
55  ComplexType phase;
56  ComplexType I(0.0, 1.0);
56    
57    // associated Legendre polynomial
58 <  p = Legendre(L, M, costheta);
59 <
60 <  phase = exp(I * (ComplexType)M * (ComplexType)phi);
61 <    
63 <  return coefficient * phase * (ComplexType)p;
58 >  p = Ptilde(L, M, costheta);
59 >  ComplexType phase(0.0, (RealType)M * phi);    
60 >
61 >  return exp(phase) * (ComplexType)p;
62    
63   }
66
67 //---------------------------------------------------------------------------//
64   //
65 < // RealType LegendreP (int l, int m, RealType x);
65 > // Routine to calculate the associated Legendre polynomials for m>=0
66   //
67 < // Computes the value of the associated Legendre polynomial P_lm (x)
68 < // of order l at a given point.
69 < //
70 < // Input:
71 < //   l  = degree of the polynomial  >= 0
72 < //   m  = parameter satisfying 0 <= m <= l,
73 < //   x  = point in which the computation is performed, range -1 <= x <= 1.
74 < // Returns:
79 < //   value of the polynomial in x
80 < //
81 < //---------------------------------------------------------------------------//
82 < RealType SphericalHarmonic::LegendreP (int l, int m, RealType x) {
83 <  // check parameters
84 <  if (m < 0 || m > l || fabs(x) > 1.0) {
85 <    printf("LegendreP got a bad argument: l = %d\tm = %d\tx = %lf\n", l, m, x);
67 > RealType SphericalHarmonic::LegendreP(int l,int m, RealType x) {
68 >
69 >  RealType temp1, temp2, temp3, temp4, result;
70 >  RealType temp5;
71 >  int i, ll;
72 >  
73 >  if (fabs(x) > 1.0) {
74 >    printf("LegendreP: x out of range: l = %d\tm = %d\tx = %lf\n", l, m, x);
75      return std::numeric_limits <RealType>:: quiet_NaN();
76    }
77    
78 <  RealType pmm = 1.0;
79 <  if (m > 0) {
80 <    RealType h = sqrt((1.0-x)*(1.0+x)),
92 <      f = 1.0;
93 <    for (int i = 1; i <= m; i++) {
94 <      pmm *= -f * h;
95 <      f += 2.0;
96 <    }
78 >  if (m>l) {
79 >    printf("LegendreP: m > l: l = %d\tm = %d\tx = %lf\n", l, m, x);
80 >    return std::numeric_limits <RealType>:: quiet_NaN();
81    }
82 <  if (l == m)
83 <    return pmm;
84 <  else {
85 <    RealType pmmp1 = x * (2 * m + 1) * pmm;
86 <    if (l == (m+1))
87 <      return pmmp1;
88 <    else {
89 <      RealType pll = 0.0;
90 <      for (int ll = m+2; ll <= l; ll++) {
91 <        pll = (x * (2 * ll - 1) * pmmp1 - (ll + m - 1) * pmm) / (ll - m);
92 <        pmm = pmmp1;
93 <        pmmp1 = pll;
82 >    
83 >  if (m<0) {
84 >    printf("LegendreP: m < 0: l = %d\tm = %d\tx = %lf\n", l, m, x);
85 >    return std::numeric_limits <RealType>:: quiet_NaN();
86 >  } else {
87 >    temp3=1.0;
88 >    
89 >    if (m>0) {
90 >      temp1=sqrt(1.0-pow(x,2));
91 >      temp5 = 1.0;
92 >      for (i=1;i<=m;++i) {
93 >        temp3 *= -temp5*temp1;
94 >        temp5 += 2.0;
95        }
111      return pll;
96      }
97 +    if (l==m) {
98 +      result = temp3;
99 +    } else {
100 +      temp4=x*(2.*m+1.)*temp3;
101 +      if (l==(m+1)) {
102 +        result = temp4;
103 +      } else {
104 +        for (ll=(m+2);ll<=l;++ll) {
105 +          temp2 = (x*(2.*ll-1.)*temp4-(ll+m-1.)*temp3)/(RealType)(ll-m);
106 +          temp3=temp4;
107 +          temp4=temp2;
108 +        }
109 +        result = temp2;
110 +      }
111 +    }
112    }
113 +  return result;
114   }
115  
116 +
117   //
118   // Routine to calculate the associated Legendre polynomials for all m...
119   //
# Line 124 | Line 125 | RealType SphericalHarmonic::Legendre(int l, int m, Rea
125    } else if (m >= 0) {
126      result = LegendreP(l,m,x);
127    } else {
128 +    //result = mpow(-m)*LegendreP(l,-m,x);
129      result = mpow(-m)*Fact(l+m)/Fact(l-m)*LegendreP(l, -m, x);
130    }
131    result *=mpow(m);
132    return result;
133   }
134   //
135 + // Routine to calculate the normalized associated Legendre polynomials...
136 + //
137 + RealType SphericalHarmonic::Ptilde(int l,int m, RealType x){
138 +
139 +  RealType result;
140 +  if (m>l || m<-l) {
141 +    result = 0.;
142 +  } else {
143 +    RealType y=(RealType)(2.*l+1.)*Fact(l-m)/Fact(l+m);
144 +    result = mpow(m) * sqrt(y) * Legendre(l,m,x) / sqrt(4.0*M_PI);
145 +  }
146 +  return result;
147 + }
148 + //
149   // mpow returns (-1)**m
150   //
151   RealType SphericalHarmonic::mpow(int m) {

Comparing:
trunk/src/math/SphericalHarmonic.cpp (property svn:keywords), Revision 1042 by gezelter, Wed Sep 20 22:16:23 2006 UTC vs.
branches/development/src/math/SphericalHarmonic.cpp (property svn:keywords), Revision 1465 by chuckv, Fri Jul 9 23:08:25 2010 UTC

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