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Geant4/processes/hadronic/util/src/G4Bessel.cc

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Diff markup

Differences between /processes/hadronic/util/src/G4Bessel.cc (Version 11.3.0) and /processes/hadronic/util/src/G4Bessel.cc (Version 9.6.p3)


  1 //                                                  1 //
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 17 // *                                               17 // *                                                                  *
 18 // * This  code  implementation is the result      18 // * This  code  implementation is the result of  the  scientific and *
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 20 // *                                               20 // *                                                                  *
 21 // * Parts of this code which have been  devel     21 // * Parts of this code which have been  developed by QinetiQ Ltd     *
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 33 // * acceptance of all terms of the Geant4 Sof     33 // * acceptance of all terms of the Geant4 Software license.          *
 34 // *******************************************     34 // ********************************************************************
 35 //                                                 35 //
 36 // %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%     36 // %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 37 //                                                 37 //
 38 // MODULE:    G4Bessel.cc                          38 // MODULE:    G4Bessel.cc
 39 //                                                 39 //
 40 // Version:   B.1                                  40 // Version:   B.1
 41 // Date:    15/04/04                               41 // Date:    15/04/04
 42 // Author:    P R Truscott                         42 // Author:    P R Truscott
 43 // Organisation:  QinetiQ Ltd, UK                  43 // Organisation:  QinetiQ Ltd, UK
 44 // Customer:    ESA/ESTEC, NOORDWIJK               44 // Customer:    ESA/ESTEC, NOORDWIJK
 45 // Contract:    17191/03/NL/LvH                    45 // Contract:    17191/03/NL/LvH
 46 //                                                 46 //
 47 // %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%     47 // %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 48 //                                                 48 //
 49 // CHANGE HISTORY                                  49 // CHANGE HISTORY
 50 // --------------                                  50 // --------------
 51 //                                                 51 //
 52 // 18 Noevmber 2003, P R Truscott, QinetiQ Ltd     52 // 18 Noevmber 2003, P R Truscott, QinetiQ Ltd, UK
 53 // Created.                                        53 // Created.
 54 //                                                 54 //
 55 // 15 March 2004, P R Truscott, QinetiQ Ltd, U     55 // 15 March 2004, P R Truscott, QinetiQ Ltd, UK
 56 // Beta release                                    56 // Beta release
 57 //                                                 57 //
 58 // 06 August 2015, A. Ribon, CERN              << 
 59 // Migrated to G4Exp, G4Log and G4Pow.         << 
 60 //                                             << 
 61 // %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%     58 // %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 62 //////////////////////////////////////////////     59 ////////////////////////////////////////////////////////////////////////////////
 63 //                                                 60 //
 64 #include "G4Bessel.hh"                             61 #include "G4Bessel.hh"
 65 #include "G4PhysicalConstants.hh"                  62 #include "G4PhysicalConstants.hh"
 66                                                << 
 67 #include "G4Exp.hh"                            << 
 68 #include "G4Log.hh"                            << 
 69 #include "G4Pow.hh"                            << 
 70 //////////////////////////////////////////////     63 ////////////////////////////////////////////////////////////////////////////////
 71 //                                                 64 //
 72 G4Bessel::G4Bessel ()                              65 G4Bessel::G4Bessel ()
 73 {;}                                                66 {;}
 74 //////////////////////////////////////////////     67 ////////////////////////////////////////////////////////////////////////////////
 75 //                                                 68 //
 76 G4Bessel::~G4Bessel ()                             69 G4Bessel::~G4Bessel ()
 77 {;}                                                70 {;}
 78 //////////////////////////////////////////////     71 ////////////////////////////////////////////////////////////////////////////////
 79 //                                                 72 //
 80 G4double G4Bessel::I0 (G4double x)                 73 G4double G4Bessel::I0 (G4double x)
 81 {                                                  74 {
 82   const G4double P1 = 1.0,                         75   const G4double P1 = 1.0,
 83                  P2 = 3.5156229,                   76                  P2 = 3.5156229,
 84                  P3 = 3.0899424,                   77                  P3 = 3.0899424,
 85                  P4 = 1.2067492,                   78                  P4 = 1.2067492,
 86                  P5 = 0.2659732,                   79                  P5 = 0.2659732,
 87                  P6 = 0.0360768,                   80                  P6 = 0.0360768,
 88                  P7 = 0.0045813;                   81                  P7 = 0.0045813;
 89   const G4double Q1 = 0.39894228,                  82   const G4double Q1 = 0.39894228,
 90                  Q2 = 0.01328592,                  83                  Q2 = 0.01328592,
 91                  Q3 = 0.00225319,                  84                  Q3 = 0.00225319,
 92                  Q4 =-0.00157565,                  85                  Q4 =-0.00157565,
 93                  Q5 = 0.00916281,                  86                  Q5 = 0.00916281,
 94                  Q6 =-0.02057706,                  87                  Q6 =-0.02057706,
 95                  Q7 = 0.02635537,                  88                  Q7 = 0.02635537,
 96                  Q8 =-0.01647633,                  89                  Q8 =-0.01647633,
 97                  Q9 = 0.00392377;                  90                  Q9 = 0.00392377;
 98                                                    91   
 99   G4double I = 0.0;                                92   G4double I = 0.0;
100   if (std::abs(x) < 3.75)                      <<  93   if (std::fabs(x) < 3.75)
101   {                                                94   {
102     G4double y = G4Pow::GetInstance()->powN(x/ <<  95     G4double y = std::pow(x/3.75, 2.0);
103     I = P1+y*(P2+y*(P3+y*(P4+y*(P5+y*(P6+y*P7)     96     I = P1+y*(P2+y*(P3+y*(P4+y*(P5+y*(P6+y*P7)))));
104   }                                                97   }
105   else                                             98   else
106   {                                                99   {
107     G4double ax = std::abs(x);                 << 100     G4double ax = std::fabs(x);
108     G4double y  = 3.75/ax;                        101     G4double y  = 3.75/ax;
109     I  = G4Exp(ax) / std::sqrt(ax) *           << 102     I  = std::exp(ax) / std::sqrt(ax) *
110       (Q1+y*(Q2+y*(Q3+y*(Q4+y*(Q5+y*(Q6+y*(Q7+    103       (Q1+y*(Q2+y*(Q3+y*(Q4+y*(Q5+y*(Q6+y*(Q7+y*(Q8+y*Q9))))))));
111   }                                               104   }
112   return I;                                       105   return I;
113 }                                                 106 }
114 //////////////////////////////////////////////    107 ////////////////////////////////////////////////////////////////////////////////
115 //                                                108 //
116 G4double G4Bessel::K0 (G4double x)                109 G4double G4Bessel::K0 (G4double x)
117 {                                                 110 {
118   const G4double P1 =-0.57721566,                 111   const G4double P1 =-0.57721566,
119                  P2 = 0.42278420,                 112                  P2 = 0.42278420,
120                  P3 = 0.23069756,                 113                  P3 = 0.23069756,
121                  P4 = 0.03488590,                 114                  P4 = 0.03488590,
122                  P5 = 0.00262698,                 115                  P5 = 0.00262698,
123                  P6 = 0.00010750,                 116                  P6 = 0.00010750,
124                  P7 = 0.00000740;                 117                  P7 = 0.00000740;
125   const G4double Q1 = 1.25331414,                 118   const G4double Q1 = 1.25331414,
126                  Q2 =-0.07832358,                 119                  Q2 =-0.07832358,
127                  Q3 = 0.02189568,                 120                  Q3 = 0.02189568,
128                  Q4 =-0.01062446,                 121                  Q4 =-0.01062446,
129                  Q5 = 0.00587872,                 122                  Q5 = 0.00587872,
130                  Q6 =-0.00251540,                 123                  Q6 =-0.00251540,
131                  Q7 = 0.00053208;                 124                  Q7 = 0.00053208;
132                                                   125 
133   G4double K = 0.0;                               126   G4double K = 0.0;
134   if (x <= 2.0)                                   127   if (x <= 2.0)
135   {                                               128   {
136     G4double y = x * x / 4.0;                     129     G4double y = x * x / 4.0;
137     K = (-G4Log(x/2.0)) * I0(x) +              << 130     K = (-std::log(x/2.0)) * I0(x) +
138       P1+y*(P2+y*(P3+y*(P4+y*(P5+y*(P6+y*P7)))    131       P1+y*(P2+y*(P3+y*(P4+y*(P5+y*(P6+y*P7)))));
139   }                                               132   }
140   else                                            133   else
141   {                                               134   {
142     G4double y = 2.0 / x;                         135     G4double y = 2.0 / x;
143     K = G4Exp(-x)  / std::sqrt(x) *            << 136     K = std::exp(-x)  / std::sqrt(x) *
144       (Q1+y*(Q2+y*(Q3+y*(Q4+y*(Q5+y*(Q6+y*Q7))    137       (Q1+y*(Q2+y*(Q3+y*(Q4+y*(Q5+y*(Q6+y*Q7))))));
145   }                                               138   }
146   return K;                                       139   return K;
147 }                                                 140 }
148 //////////////////////////////////////////////    141 ////////////////////////////////////////////////////////////////////////////////
149 //                                                142 //
150 G4double G4Bessel::I1 (G4double x)                143 G4double G4Bessel::I1 (G4double x)
151 {                                                 144 {
152   const G4double P1 = 0.5,                        145   const G4double P1 = 0.5,
153                  P2 = 0.87890594,                 146                  P2 = 0.87890594,
154                  P3 = 0.51498869,                 147                  P3 = 0.51498869,
155                  P4 = 0.15084934,                 148                  P4 = 0.15084934,
156                  P5 = 0.02658733,                 149                  P5 = 0.02658733,
157                  P6 = 0.00301532,                 150                  P6 = 0.00301532,
158                  P7 = 0.00032411;                 151                  P7 = 0.00032411;
159   const G4double Q1 = 0.39894228,                 152   const G4double Q1 = 0.39894228,
160                  Q2 =-0.03988024,                 153                  Q2 =-0.03988024,
161                  Q3 =-0.00362018,                 154                  Q3 =-0.00362018,
162                  Q4 = 0.00163801,                 155                  Q4 = 0.00163801,
163                  Q5 =-0.01031555,                 156                  Q5 =-0.01031555,
164                  Q6 = 0.02282967,                 157                  Q6 = 0.02282967,
165                  Q7 =-0.02895312,                 158                  Q7 =-0.02895312,
166                  Q8 = 0.01787654,                 159                  Q8 = 0.01787654,
167                  Q9 =-0.00420059;                 160                  Q9 =-0.00420059;
168                                                   161 
169   G4double I = 0.0;                               162   G4double I = 0.0;
170   if (std::abs(x) < 3.75)                      << 163   if (std::fabs(x) < 3.75)
171   {                                               164   {
172     G4double ax = std::abs(x);                 << 165     G4double ax = std::fabs(x);
173     G4double y = G4Pow::GetInstance()->powN(x/ << 166     G4double y = std::pow(x/3.75, 2.0);
174     I = ax*(P1+y*(P2+y*(P3+y*(P4+y*(P5+y*(P6+y    167     I = ax*(P1+y*(P2+y*(P3+y*(P4+y*(P5+y*(P6+y*P7))))));
175   }                                               168   }
176   else                                            169   else
177   {                                               170   {
178     G4double ax = std::abs(x);                 << 171     G4double ax = std::fabs(x);
179     G4double y  = 3.75/ax;                        172     G4double y  = 3.75/ax;
180     I  = G4Exp(ax) / std::sqrt(ax) *           << 173     I  = std::exp(ax) / std::sqrt(ax) *
181       (Q1+y*(Q2+y*(Q3+y*(Q4+y*(Q5+y*(Q6+y*(Q7+    174       (Q1+y*(Q2+y*(Q3+y*(Q4+y*(Q5+y*(Q6+y*(Q7+y*(Q8+y*Q9))))))));
182   }                                               175   }
183   if (x < 0.0) I = -I;                            176   if (x < 0.0) I = -I;
184   return I;                                       177   return I;
185 }                                                 178 }
186 //////////////////////////////////////////////    179 ////////////////////////////////////////////////////////////////////////////////
187 //                                                180 //
188 G4double G4Bessel::K1 (G4double x)                181 G4double G4Bessel::K1 (G4double x)
189 {                                                 182 {
190   const G4double P1 = 1.0,                        183   const G4double P1 = 1.0,
191                  P2 = 0.15443144,                 184                  P2 = 0.15443144,
192                  P3 =-0.67278579,                 185                  P3 =-0.67278579,
193                  P4 =-0.18156897,                 186                  P4 =-0.18156897,
194                  P5 =-0.01919402,                 187                  P5 =-0.01919402,
195                  P6 =-0.00110404,                 188                  P6 =-0.00110404,
196                  P7 =-0.00004686;                 189                  P7 =-0.00004686;
197   const G4double Q1 = 1.25331414,                 190   const G4double Q1 = 1.25331414,
198                  Q2 = 0.23498619,                 191                  Q2 = 0.23498619,
199                  Q3 =-0.03655620,                 192                  Q3 =-0.03655620,
200                  Q4 = 0.01504268,                 193                  Q4 = 0.01504268,
201                  Q5 =-0.00780353,                 194                  Q5 =-0.00780353,
202                  Q6 = 0.00325614,                 195                  Q6 = 0.00325614,
203                  Q7 =-0.00068245;                 196                  Q7 =-0.00068245;
204                                                   197 
205   G4double K = 0.0;                               198   G4double K = 0.0;
206   if (x <= 2.0)                                   199   if (x <= 2.0)
207   {                                               200   {
208     G4double y = x * x / 4.0;                     201     G4double y = x * x / 4.0;
209     K = G4Log(x/2.0)*I1(x) + 1.0/x *           << 202     K = std::log(x/2.0)*I1(x) + 1.0/x *
210       (P1+y*(P2+y*(P3+y*(P4+y*(P5+y*(P6+y*P7))    203       (P1+y*(P2+y*(P3+y*(P4+y*(P5+y*(P6+y*P7))))));
211   }                                               204   }
212   else                                            205   else
213   {                                               206   {
214     G4double y = 2.0 / x;                         207     G4double y = 2.0 / x;
215     K = G4Exp(-x) / std::sqrt(x) *             << 208     K = std::exp(-x) / std::sqrt(x) *
216       (Q1+y*(Q2+y*(Q3+y*(Q4+y*(Q5+y*(Q6+y*Q7))    209       (Q1+y*(Q2+y*(Q3+y*(Q4+y*(Q5+y*(Q6+y*Q7))))));
217   }                                               210   }
218   return K;                                       211   return K;
219 }                                                 212 }
220 //////////////////////////////////////////////    213 ////////////////////////////////////////////////////////////////////////////////
221 //                                                214 //
222 G4double G4Bessel::pI0 (G4double x)               215 G4double G4Bessel::pI0 (G4double x)
223 {                                                 216 {
224   const G4double A0  = 0.1250000000000E+00,       217   const G4double A0  = 0.1250000000000E+00,
225                  A1  = 7.0312500000000E-02,       218                  A1  = 7.0312500000000E-02,
226                  A2  = 7.3242187500000E-02,       219                  A2  = 7.3242187500000E-02,
227                  A3  = 1.1215209960938E-01,       220                  A3  = 1.1215209960938E-01,
228                  A4  = 2.2710800170898E-01,       221                  A4  = 2.2710800170898E-01,
229                  A5  = 5.7250142097473E-01,       222                  A5  = 5.7250142097473E-01,
230                  A6  = 1.7277275025845E+00,       223                  A6  = 1.7277275025845E+00,
231                  A7  = 6.0740420012735E+00,       224                  A7  = 6.0740420012735E+00,
232                  A8  = 2.4380529699556E+01,       225                  A8  = 2.4380529699556E+01,
233                  A9  = 1.1001714026925E+02,       226                  A9  = 1.1001714026925E+02,
234                  A10 = 5.5133589612202E+02,       227                  A10 = 5.5133589612202E+02,
235                  A11 = 3.0380905109224E+03;       228                  A11 = 3.0380905109224E+03;
236                                                   229 
237   G4double I = 0.0;                               230   G4double I = 0.0;
238   if (x == 0.0)                                   231   if (x == 0.0)
239   {                                               232   {
240     I = 1.0;                                      233     I = 1.0;
241   }                                               234   }
242   else if (x < 18.0)                              235   else if (x < 18.0)
243   {                                               236   {
244     I          = 1.0;                             237     I          = 1.0;
245     G4double y = x * x;                           238     G4double y = x * x;
246     G4double q = 1.0;                             239     G4double q = 1.0;
247     for (G4int i=1; i<101; i++)                   240     for (G4int i=1; i<101; i++)
248     {                                             241     {
249       q *= 0.25 * y / i / i;                      242       q *= 0.25 * y / i / i;
250       I += q;                                     243       I += q;
251       if (std::abs(q/I) < 1.0E-15) break;         244       if (std::abs(q/I) < 1.0E-15) break;
252     }                                             245     }
253   }                                               246   }
254   else                                            247   else
255   {                                               248   {
256     G4double y = 1.0 / x;                         249     G4double y = 1.0 / x;
257     I = G4Exp(x) / std::sqrt(twopi*x) *        << 250     I = std::exp(x) / std::sqrt(twopi*x) *
258       (1.0 + y*(A0+y*(A1+y*(A2+y*(A3+y*(A4+y*(    251       (1.0 + y*(A0+y*(A1+y*(A2+y*(A3+y*(A4+y*(A5+y*(A6+y*(A7+y*(A8+y*(A9+y*(A10+y*A11))))))))))));
259   }                                               252   }
260                                                   253 
261   return I;                                       254   return I;
262 }                                                 255 }
263 //////////////////////////////////////////////    256 ////////////////////////////////////////////////////////////////////////////////
264 //                                                257 //
265 G4double G4Bessel::pI1 (G4double x)               258 G4double G4Bessel::pI1 (G4double x)
266 {                                                 259 {
267   const G4double A0  = -0.3750000000000E+00,      260   const G4double A0  = -0.3750000000000E+00,
268                  A1  = -1.1718750000000E-01,      261                  A1  = -1.1718750000000E-01,
269                  A2  = -1.0253906250000E-01,      262                  A2  = -1.0253906250000E-01,
270                  A3  = -1.4419555664063E-01,      263                  A3  = -1.4419555664063E-01,
271                  A4  = -2.775764465332E-01,       264                  A4  = -2.775764465332E-01,
272                  A5  = -6.7659258842468E-01,      265                  A5  = -6.7659258842468E-01,
273                  A6  = -1.9935317337513E+00,      266                  A6  = -1.9935317337513E+00,
274                  A7  = -6.8839142681099E+00,      267                  A7  = -6.8839142681099E+00,
275                  A8  = -2.7248827311269E+01,      268                  A8  = -2.7248827311269E+01,
276                  A9  = -1.2159789187654E+02,      269                  A9  = -1.2159789187654E+02,
277                  A10 = -6.0384407670507E+02,      270                  A10 = -6.0384407670507E+02,
278                  A11 = -3.3022722944809E+03;      271                  A11 = -3.3022722944809E+03;
279                                                   272 
280   G4double I = 0.0;                               273   G4double I = 0.0;
281   if (x == 0.0)                                   274   if (x == 0.0)
282   {                                               275   {
283     I = 0.0;                                      276     I = 0.0;
284   }                                               277   }
285   else if (x < 18.0)                              278   else if (x < 18.0)
286   {                                               279   {
287     I          = 1.0;                             280     I          = 1.0;
288     G4double y = x * x;                           281     G4double y = x * x;
289     G4double q = 1.0;                             282     G4double q = 1.0;
290     for (G4int i=1; i<101; i++)                   283     for (G4int i=1; i<101; i++)
291     {                                             284     {
292       q *= 0.25 * y / i / (i+1.0);                285       q *= 0.25 * y / i / (i+1.0);
293       I += q;                                     286       I += q;
294       if (std::abs(q/I) < 1.0E-15) break;         287       if (std::abs(q/I) < 1.0E-15) break;
295     }                                             288     }
296     I *= 0.5 * x;                                 289     I *= 0.5 * x;
297                                                   290     
298   }                                               291   }
299   else                                            292   else
300   {                                               293   {
301     G4double y = 1.0 / x;                         294     G4double y = 1.0 / x;
302     I = G4Exp(x) / std::sqrt(twopi*x) *        << 295     I = std::exp(x) / std::sqrt(twopi*x) *
303       (1.0 + y*(A0+y*(A1+y*(A2+y*(A3+y*(A4+y*(    296       (1.0 + y*(A0+y*(A1+y*(A2+y*(A3+y*(A4+y*(A5+y*(A6+y*(A7+y*(A8+y*(A9+y*(A10+y*A11))))))))))));
304   }                                               297   }
305                                                   298 
306   return I;                                       299   return I;
307 }                                                 300 }
308 //////////////////////////////////////////////    301 ////////////////////////////////////////////////////////////////////////////////
309 //                                                302 //
310 G4double G4Bessel::pK0 (G4double x)               303 G4double G4Bessel::pK0 (G4double x)
311 {                                                 304 {
312   const G4double A0 = 0.1250000000000E+00,        305   const G4double A0 = 0.1250000000000E+00,
313                  A1 = 0.2109375000000E+00,        306                  A1 = 0.2109375000000E+00,
314                  A2 = 1.0986328125000E+00,        307                  A2 = 1.0986328125000E+00,
315                  A3 = 1.1775970458984E+01,        308                  A3 = 1.1775970458984E+01,
316                  A4 = 2.1461706161499E+02,        309                  A4 = 2.1461706161499E+02,
317                  A5 = 5.9511522710323E+03,        310                  A5 = 5.9511522710323E+03,
318                  A6 = 2.3347645606175E+05,        311                  A6 = 2.3347645606175E+05,
319                  A7 = 1.2312234987631E+07;        312                  A7 = 1.2312234987631E+07;
320                                                   313 
321   G4double K = 0.0;                               314   G4double K = 0.0;
322   if (x == 0.0)                                   315   if (x == 0.0)
323   {                                               316   {
324     K = 1.0E+307;                                 317     K = 1.0E+307;
325   }                                               318   }
326   else if (x < 9.0)                               319   else if (x < 9.0)
327   {                                               320   {
328     G4double y = x * x;                           321     G4double y = x * x;
329     G4double C = -G4Log(x/2.0) - 0.57721566490 << 322     G4double C = -std::log(x/2.0) - 0.5772156649015329;
330     G4double q = 1.0;                             323     G4double q = 1.0;
331     G4double t = 0.0;                             324     G4double t = 0.0;
332     for (G4int i=1; i<51; i++)                    325     for (G4int i=1; i<51; i++)
333     {                                             326     {
334       q *= 0.25 * y / i / i;                      327       q *= 0.25 * y / i / i;
335       t += 1.0 / i ;                              328       t += 1.0 / i ;
336       K += q * (t+C);                             329       K += q * (t+C);
337     }                                             330     }
338     K += C;                                       331     K += C;
339   }                                               332   }
340   else                                            333   else
341   {                                               334   {
342     G4double y = 1.0 / x / x;                     335     G4double y = 1.0 / x / x;
343     K = 0.5 / x / pI0(x) *                        336     K = 0.5 / x / pI0(x) *
344       (1.0 + y*(A0+y*(A1+y*(A2+y*(A3+y*(A4+y*(    337       (1.0 + y*(A0+y*(A1+y*(A2+y*(A3+y*(A4+y*(A5+y*(A6+y*A7))))))));
345   }                                               338   }
346                                                   339   
347   return K;                                       340   return K;
348 }                                                 341 }
349 //////////////////////////////////////////////    342 ////////////////////////////////////////////////////////////////////////////////
350 //                                                343 //
351 G4double G4Bessel::pK1 (G4double x)               344 G4double G4Bessel::pK1 (G4double x)
352 {                                                 345 {
353   G4double K = 0.0;                               346   G4double K = 0.0;
354   if (x == 0.0)                                   347   if (x == 0.0)
355     K = 1.0E+307;                                 348     K = 1.0E+307;
356   else                                            349   else
357     K = (1.0/x - pI1(x)*pK0(x)) / pI0(x);         350     K = (1.0/x - pI1(x)*pK0(x)) / pI0(x);
358   return K;                                       351   return K;
359 }                                                 352 }
360 //////////////////////////////////////////////    353 ////////////////////////////////////////////////////////////////////////////////
361 //                                                354 //
362                                                   355