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1 // 1 2 // ******************************************* 3 // * License and Disclaimer 4 // * 5 // * The Geant4 software is copyright of th 6 // * the Geant4 Collaboration. It is provided 7 // * conditions of the Geant4 Software License 8 // * LICENSE and available at http://cern.ch/ 9 // * include a list of copyright holders. 10 // * 11 // * Neither the authors of this software syst 12 // * institutes,nor the agencies providing fin 13 // * work make any representation or warran 14 // * regarding this software system or assum 15 // * use. Please see the license in the file 16 // * for the full disclaimer and the limitatio 17 // * 18 // * This code implementation is the result 19 // * technical work of the GEANT4 collaboratio 20 // * By using, copying, modifying or distri 21 // * any work based on the software) you ag 22 // * use in resulting scientific publicati 23 // * acceptance of all terms of the Geant4 Sof 24 // ******************************************* 25 // 26 // G4DormandPrinceRK56 implementation 27 // 28 // Created: Somnath Banerjee, Google Summer of 29 // Supervision: John Apostolakis, CERN 30 // ------------------------------------------- 31 32 #include "G4DormandPrinceRK56.hh" 33 #include "G4LineSection.hh" 34 35 // Constructor 36 // 37 G4DormandPrinceRK56::G4DormandPrinceRK56(G4Equ 38 G4int 39 G4boo 40 : G4MagIntegratorStepper(EqRhs, noIntegratio 41 { 42 const G4int numberOfVariables = noIntegrat 43 44 // New Chunk of memory being created for u 45 46 // aki - for storing intermediate RHS 47 // 48 ak2 = new G4double[numberOfVariables]; 49 ak3 = new G4double[numberOfVariables]; 50 ak4 = new G4double[numberOfVariables]; 51 ak5 = new G4double[numberOfVariables]; 52 ak6 = new G4double[numberOfVariables]; 53 ak7 = new G4double[numberOfVariables]; 54 ak8 = new G4double[numberOfVariables]; 55 ak9 = new G4double[numberOfVariables]; 56 57 // Memory for Additional stages 58 // 59 ak10 = new G4double[numberOfVariables]; 60 ak11 = new G4double[numberOfVariables]; 61 ak12 = new G4double[numberOfVariables]; 62 ak10_low = new G4double[numberOfVariables] 63 64 const G4int numStateVars = std::max(noInte 65 yTemp = new G4double[numStateVars]; 66 yIn = new G4double[numStateVars] ; 67 68 fLastInitialVector = new G4double[numState 69 fLastFinalVector = new G4double[numStateVa 70 71 fLastDyDx = new G4double[numStateVars]; 72 73 fMidVector = new G4double[numStateVars]; 74 fMidError = new G4double[numStateVars]; 75 76 if( primary ) 77 { 78 fAuxStepper = new G4DormandPrinceRK56(Eq 79 } 80 } 81 82 // Destructor 83 // 84 G4DormandPrinceRK56::~G4DormandPrinceRK56() 85 { 86 // clear all previously allocated memory f 87 88 delete [] ak2; 89 delete [] ak3; 90 delete [] ak4; 91 delete [] ak5; 92 delete [] ak6; 93 delete [] ak7; 94 delete [] ak8; 95 delete [] ak9; 96 97 delete [] ak10; 98 delete [] ak10_low; 99 delete [] ak11; 100 delete [] ak12; 101 102 delete [] yTemp; 103 delete [] yIn; 104 105 delete [] fLastInitialVector; 106 delete [] fLastFinalVector; 107 delete [] fLastDyDx; 108 delete [] fMidVector; 109 delete [] fMidError; 110 111 delete fAuxStepper; 112 } 113 114 // Stepper 115 // 116 // Passing in the value of yInput[],the first 117 // Giving back yOut and yErr arrays for output 118 // 119 void G4DormandPrinceRK56::Stepper(const G4doub 120 const G4doub 121 G4doub 122 G4doub 123 G4doub 124 // G4double 125 // endpoint 126 { 127 G4int i; 128 129 // The various constants defined on the ba 130 // Old Coefficients from 131 // P.J.Prince and J.R.Dormand, "High order 132 // Journal of Computational and Applied Ma 133 // 134 const G4double b21 = 1.0/10.0 , 135 b31 = -2.0/81.0 , 136 b32 = 20.0/81.0 , 137 138 b41 = 615.0/1372.0 , 139 b42 = -270.0/343.0 , 140 b43 = 1053.0/1372.0 , 141 142 b51 = 3243.0/5500.0 , 143 b52 = -54.0/55.0 , 144 b53 = 50949.0/71500.0 , 145 b54 = 4998.0/17875.0 , 146 147 b61 = -26492.0/37125.0 , 148 b62 = 72.0/55.0 , 149 b63 = 2808.0/23375.0 , 150 b64 = -24206.0/37125.0 , 151 b65 = 338.0/459.0 , 152 153 b71 = 5561.0/2376.0 , 154 b72 = -35.0/11.0 , 155 b73 = -24117.0/31603.0 , 156 b74 = 899983.0/200772.0 , 157 b75 = -5225.0/1836.0 , 158 b76 = 3925.0/4056.0 , 159 160 b81 = 465467.0/266112.0 , 161 b82 = -2945.0/1232.0 , 162 b83 = -5610201.0/14158144.0 163 b84 = 10513573.0/3212352.0 164 b85 = -424325.0/205632.0 , 165 b86 = 376225.0/454272.0 , 166 b87 = 0.0 , 167 168 c1 = 61.0/864.0 , 169 c2 = 0.0 , 170 c3 = 98415.0/321776.0 , 171 c4 = 16807.0/146016.0 , 172 c5 = 1375.0/7344.0 , 173 c6 = 1375.0/5408.0 , 174 c7 = -37.0/1120.0 , 175 c8 = 1.0/10.0 , 176 177 b91 = 61.0/864.0 , 178 b92 = 0.0 , 179 b93 = 98415.0/321776.0 , 180 b94 = 16807.0/146016.0 , 181 b95 = 1375.0/7344.0 , 182 b96 = 1375.0/5408.0 , 183 b97 = -37.0/1120.0 , 184 b98 = 1.0/10.0 , 185 186 dc1 = c1 - 821.0/10800.0 187 dc2 = c2 - 0.0 , 188 dc3 = c3 - 19683.0/71825, 189 dc4 = c4 - 175273.0/912600 190 dc5 = c5 - 395.0/3672.0 , 191 dc6 = c6 - 785.0/2704.0 , 192 dc7 = c7 - 3.0/50.0 , 193 dc8 = c8 - 0.0 , 194 dc9 = 0.0; 195 196 197 // New Coefficients obtained from 198 // Table 3 RK6(5)9FM with corrected coefficien 199 // 200 // T. S. Baker, J. R. Dormand, J. P. Gilmor 201 // "Continuous approximation with embedded 202 // Applied Numerical Mathematics, vol. 22, 203 // 204 // b21 = 1.0/9.0 , 205 // 206 // b31 = 1.0/24.0 , 207 // b32 = 1.0/8.0 , 208 // 209 // b41 = 1.0/16.0 , 210 // b42 = 0.0 , 211 // b43 = 3.0/16.0 , 212 // 213 // b51 = 280.0/729.0 , 214 // b52 = 0.0 , 215 // b53 = -325.0/243.0 , 216 // b54 = 1100.0/729.0 , 217 // 218 // b61 = 6127.0/14680.0 , 219 // b62 = 0.0 , 220 // b63 = -1077.0/734.0 , 221 // b64 = 6494.0/4037.0 , 222 // b65 = -9477.0/161480.0 , 223 // 224 // b71 = -13426273320.0/14809773769.0 , 225 // b72 = 0.0 , 226 // b73 = 4192558704.0/2115681967.0 , 227 // b74 = 14334750144.0/14809773769.0 , 228 // b75 = 117092732328.0/14809773769.0 , 229 // b76 = -361966176.0/40353607.0 , 230 // 231 // b81 = -2340689.0/1901060.0 , 232 // b82 = 0.0 , 233 // b83 = 31647.0/13579.0 , 234 // b84 = 253549596.0/149518369.0 , 235 // b85 = 10559024082.0/977620105.0 , 236 // b86 = -152952.0/12173.0 , 237 // b87 = -5764801.0/186010396.0 , 238 // 239 // b91 = 203.0/2880.0 , 240 // b92 = 0.0 , 241 // b93 = 0.0 , 242 // b94 = 30208.0/70785.0 , 243 // b95 = 177147.0/164560.0 , 244 // b96 = -536.0/705.0 , 245 // b97 = 1977326743.0/3619661760.0 , 246 // b98 = -259.0/720.0 , 247 // 248 // 249 // dc1 = 36567.0/458800.0 - b91, 250 // dc2 = 0.0 - b92, 251 // dc3 = 0.0 - b93, 252 // dc4 = 9925984.0/27063465.0 - b94, 253 // dc5 = 85382667.0/117968950.0 - b95, 254 // dc6 = - 310378.0/808635.0 - b96 , 255 // dc7 = 262119736669.0/345979336560.0 - b 256 // dc8 = - 1.0/2.0 - b98 , 257 // dc9 = -101.0/2294.0 ; 258 259 // end of declaration 260 261 const G4int numberOfVariables = GetNumberO 262 263 // The number of variables to be integrate 264 // 265 yOut[7] = yTemp[7] = yIn[7] = yInput[7]; 266 267 // Saving yInput because yInput and yOut 268 // 269 for(i=0; i<numberOfVariables; ++i) 270 { 271 yIn[i]=yInput[i]; 272 } 273 // RightHandSide(yIn, dydx) ; // 1st Stage 274 275 for(i=0; i<numberOfVariables; ++i) 276 { 277 yTemp[i] = yIn[i] + b21*Step*dydx[i] ; 278 } 279 RightHandSide(yTemp, ak2) ; / 280 281 for(i=0; i<numberOfVariables; ++i) 282 { 283 yTemp[i] = yIn[i] + Step*(b31*dydx[i] 284 } 285 RightHandSide(yTemp, ak3) ; / 286 287 for(i=0; i<numberOfVariables; ++i) 288 { 289 yTemp[i] = yIn[i] + Step*(b41*dydx[i] 290 } 291 RightHandSide(yTemp, ak4) ; / 292 293 for(i=0; i<numberOfVariables; ++i) 294 { 295 yTemp[i] = yIn[i] + Step*(b51*dydx[i] 296 b54*ak4[i]) 297 } 298 RightHandSide(yTemp, ak5) ; / 299 300 for(i=0; i<numberOfVariables; ++i) 301 { 302 yTemp[i] = yIn[i] + Step*(b61*dydx[i] 303 b64*ak4[i] + 304 } 305 RightHandSide(yTemp, ak6) ; / 306 307 for(i=0; i<numberOfVariables; ++i) 308 { 309 yTemp[i] = yIn[i] + Step*(b71*dydx[i] 310 b74*ak4[i] + 311 } 312 RightHandSide(yTemp, ak7); / 313 314 for(i=0; i<numberOfVariables; ++i) 315 { 316 yTemp[i] = yIn[i] + Step*(b81*dydx[i] 317 b84*ak4[i] + 318 b87*ak7[i]); 319 } 320 RightHandSide(yTemp, ak8); / 321 322 for(i=0; i<numberOfVariables; ++i) 323 { 324 yOut[i] = yIn[i] + Step*(b91*dydx[i] + 325 b94*ak4[i] + 326 b97*ak7[i] + 327 } 328 RightHandSide(yOut, ak9); / 329 330 331 for(i=0; i<numberOfVariables; ++i) 332 { 333 // Estimate error as difference betwee 334 // 6th order methods 335 // 336 yErr[i] = Step*( dc1*dydx[i] + dc2*ak 337 + dc5*ak5[i] + dc6*ak6 338 + dc9*ak9[i] ) ; 339 340 // Saving 'estimated' derivative at en 341 // nextDydx[i] = ak9[i]; 342 343 // Store Input and Final values, for p 344 // 345 fLastInitialVector[i] = yIn[i] ; 346 fLastFinalVector[i] = yOut[i]; 347 fLastDyDx[i] = dydx[i]; 348 } 349 350 fLastStepLength = Step; 351 352 return ; 353 } 354 355 // DistChord 356 // 357 G4double G4DormandPrinceRK56::DistChord() con 358 { 359 G4double distLine, distChord; 360 G4ThreeVector initialPoint, finalPoint, mi 361 362 // Store last initial and final points 363 // (they will be overwritten in self-Stepp 364 // 365 initialPoint = G4ThreeVector( fLastInitial 366 fLastInitialV 367 finalPoint = G4ThreeVector( fLastFinalVe 368 fLastFinalVec 369 370 // Do half a step using StepNoErr 371 372 fAuxStepper->Stepper( fLastInitialVector, 373 fMidVector, fMidErr 374 375 midPoint = G4ThreeVector( fMidVector[0], f 376 377 // Use stored values of Initial and Endpoi 378 // distance of Chord 379 // 380 if (initialPoint != finalPoint) 381 { 382 distLine = G4LineSection::Distline( m 383 distChord = distLine; 384 } 385 else 386 { 387 distChord = (midPoint-initialPoint).ma 388 } 389 return distChord; 390 } 391 392 // The following interpolation scheme has been 393 // Table 5. The RK6(5)9FM process and associat 394 // 395 // J. R. Dormand, M. A. Lockyer, N. E. McGorri 396 // "Global error estimation with runge-kutta t 397 // Computers & Mathematics with Applications, 398 // 399 // Fifth order interpolant with one extra func 400 // 401 void G4DormandPrinceRK56::SetupInterpolate_low 402 403 404 { 405 const G4int numberOfVariables= this->GetNu 406 407 G4double b_101 = 33797.0/460800.0 , 408 b_102 = 0. , 409 b_103 = 0. , 410 b_104 = 27757.0/70785.0 , 411 b_105 = 7923501.0/26329600.0 , 412 b_106 = -927.0/3760.0 , 413 b_107 = -3314760575.0/23165835264 414 b_108 = 2479.0/23040.0 , 415 b_109 = 1.0/64.0 ; 416 417 for(G4int i=0; i<numberOfVariables; ++i) 418 { 419 yIn[i]=yInput[i]; 420 } 421 422 423 for(G4int i=0; i<numberOfVariables; ++i) 424 { 425 yTemp[i] = yIn[i] + Step*(b_101*dydx[i] 426 b_104*ak4[i] + 427 b_107*ak7[i] + 428 } 429 RightHandSide(yTemp, ak10_low); / 430 } 431 432 void G4DormandPrinceRK56::Interpolate_low( con 433 con 434 con 435 436 437 { 438 G4double bf1, bf4, bf5, bf6, bf7, bf8, bf9, 439 440 G4double tau0 = tau; 441 const G4int numberOfVariables= this->GetNumb 442 443 for(G4int i=0; i<numberOfVariables; ++i) 444 { 445 yIn[i]=yInput[i]; 446 } 447 448 G4double tau_2 = tau0*tau0 , 449 tau_3 = tau0*tau_2, 450 tau_4 = tau_2*tau_2; 451 452 // bf2 = bf3 = 0.0 453 bf1 = (66480.0*tau_4-206243.0*tau_3+237786.0 454 / 28800.0 ; 455 bf4 = -16.0*tau*(45312.0*tau_3 - 125933.0*ta 456 / 70785.0 ; 457 bf5 = -2187.0*tau*(19440.0*tau_3 - 45743.0*t 458 / 1645600.0 ; 459 bf6 = tau*(12864.0*tau_3 - 30653.0*tau_2 + 2 460 / 705.0 ; 461 bf7 = -5764801.0*tau*(16464.0*tau_3 - 32797. 462 / 7239323520.0 ; 463 bf8 = 37.0*tau*(336.0*tau_3 - 661.0*tau_2 + 464 / 1440.0 ; 465 bf9 = tau*(tau-1.0)*(16.0*tau_2 - 15.0*tau + 466 / 4.0 ; 467 bf10 = 8.0*tau*(tau - 1.0)*(tau - 1.0)*(2.0* 468 469 for( G4int i=0; i<numberOfVariables; ++i) 470 { 471 yOut[i] = yIn[i] + Step*tau*( bf1*dydx[i] 472 bf6*ak6[i] + 473 bf9*ak9[i] + 474 } 475 } 476 477 // The following scheme and set of coefficient 478 // Table 2. Sixth order dense formula based on 479 // RK6(5)9FM with extra stages C1O= 1/2, C11 = 480 // 481 // T. S. Baker, J. R. Dormand, J. P. Gilmore, 482 // "Continuous approximation with embedded Run 483 // Applied Numerical Mathematics, vol. 22, no. 484 // 485 // --- Sixth order interpolant with 3 addition 486 // 487 // Function for calculating the additional sta 488 // 489 void G4DormandPrinceRK56::SetupInterpolate_hig 490 491 492 { 493 // Coefficients for the additional stages 494 // 495 G4double b101 = 33797.0/460800.0 , 496 b102 = 0.0 , 497 b103 = 0.0 , 498 b104 = 27757.0/70785.0 , 499 b105 = 7923501.0/26329600.0 , 500 b106 = -927.0/3760.0 , 501 b107 = -3314760575.0/23165835264. 502 b108 = 2479.0/23040.0 , 503 b109 = 1.0/64.0 , 504 505 b111 = 5843.0/76800.0 , 506 b112 = 0.0 , 507 b113 = 0.0 , 508 b114 = 464.0/2673.0 , 509 b115 = 353997.0/1196800.0 , 510 b116 = -15068.0/57105.0 , 511 b117 = -282475249.0/3644974080.0 512 b118 = 8678831.0/156245760.0 , 513 b119 = 116113.0/11718432.0 , 514 b1110 = -25.0/243.0 , 515 516 b121 = 15088049.0/199065600.0 , 517 b122 = 0.0 , 518 b123 = 0.0 , 519 b124 = 2.0/5.0 , 520 b125 = 92222037.0/268083200.0 , 521 b126 = -433420501.0/1528586640.0 522 b127 = -11549242677007.0/83630285 523 b128 = 2725085557.0/26167173120. 524 b129 = 235429367.0/16354483200.0 525 b1210 = -90924917.0/1040739840.0 526 b1211 = -271149.0/21414400.0 ; 527 528 const G4int numberOfVariables = GetNumberO 529 530 // Saving yInput because yInput and yOut c 531 // 532 for(G4int i=0; i<numberOfVariables; ++i) 533 { 534 yIn[i]=yInput[i]; 535 } 536 yTemp[7] = yIn[7]; 537 538 // Evaluate the extra stages 539 // 540 for(G4int i=0; i<numberOfVariables; ++i) 541 { 542 yTemp[i] = yIn[i] + Step*(b101*dydx[i] 543 b104*ak4[i] 544 b107*ak7[i] 545 } 546 RightHandSide(yTemp, ak10); 547 548 for(G4int i=0; i<numberOfVariables; ++i) 549 { 550 yTemp[i] = yIn[i] + Step*(b111*dydx[i] 551 b114*ak4[i] 552 b117*ak7[i] 553 b1110*ak10[i 554 } 555 RightHandSide(yTemp, ak11); 556 557 for(G4int i=0; i<numberOfVariables; ++i) 558 { 559 yTemp[i] = yIn[i] + Step*(b121*dydx[i] 560 b124*ak4[i] 561 b127*ak7[i] 562 b1210*ak10[i 563 } 564 RightHandSide(yTemp, ak12); 565 } 566 567 // Function to interpolate to tau(passed in) f 568 // 569 void G4DormandPrinceRK56::Interpolate_high( co 570 co 571 co 572 573 574 { 575 // Define the coefficients for the polynom 576 // 577 G4double bi[13][6], b[13]; 578 G4int numberOfVariables = GetNumberOfVaria 579 580 581 // COEFFICIENTS OF bi[ 1] 582 bi[1][0] = 1.0 , 583 bi[1][1] = -18487.0/2880.0 , 584 bi[1][2] = 139189.0/7200.0 , 585 bi[1][3] = -53923.0/1800.0 , 586 bi[1][4] = 13811.0/600, 587 bi[1][5] = -2071.0/300, 588 // -------------------------------------- 589 // 590 // COEFFICIENTS OF bi[2] 591 bi[2][0] = 0.0 , 592 bi[2][1] = 0.0 , 593 bi[2][2] = 0.0 , 594 bi[2][3] = 0.0 , 595 bi[2][4] = 0.0 , 596 bi[2][5] = 0.0 , 597 // -------------------------------------- 598 // 599 // COEFFICIENTS OF bi[3] 600 bi[3][0] = 0.0 , 601 bi[3][1] = 0.0 , 602 bi[3][2] = 0.0 , 603 bi[3][3] = 0.0 , 604 bi[3][4] = 0.0 , 605 bi[3][5] = 0.0 , 606 // -------------------------------------- 607 // 608 // COEFFICIENTS OF bi[4] 609 bi[4][0] = 0.0 , 610 bi[4][1] = -30208.0/14157.0 , 611 bi[4][2] = 1147904.0/70785.0 , 612 bi[4][3] = -241664.0/5445.0 , 613 bi[4][4] = 241664.0/4719.0 , 614 bi[4][5] = -483328.0/23595.0 , 615 // -------------------------------------- 616 // 617 // COEFFICIENTS OF bi[5] 618 bi[5][0] = 0.0 , 619 bi[5][1] = -177147.0/32912.0 , 620 bi[5][2] = 3365793.0/82280.0 , 621 bi[5][3] = -2302911.0/20570.0 , 622 bi[5][4] = 531441.0/4114.0 , 623 bi[5][5] = -531441.0/10285.0 , 624 // -------------------------------------- 625 // 626 // COEFFICIENTS OF bi[6] 627 bi[6][0] = 0.0 , 628 bi[6][1] = 536.0/141.0 , 629 bi[6][2] = -20368.0/705.0 , 630 bi[6][3] = 55744.0/705.0 , 631 bi[6][4] = -4288.0/47.0 , 632 bi[6][5] = 8576.0/235, 633 // -------------------------------------- 634 // 635 // COEFFICIENTS OF bi[7] 636 bi[7][0] = 0.0 , 637 bi[7][1] = -1977326743.0/723932352.0 , 638 bi[7][2] = 37569208117.0/1809830880.0 , 639 bi[7][3] = -1977326743.0/34804440.0 , 640 bi[7][4] = 1977326743.0/30163848.0 , 641 bi[7][5] = -1977326743.0/75409620.0 , 642 // -------------------------------------- 643 // 644 // COEFFICIENTS OF bi[8] 645 bi[8][0] = 0.0 , 646 bi[8][1] = 259.0/144.0 , 647 bi[8][2] = -4921.0/360.0 , 648 bi[8][3] = 3367.0/90.0 , 649 bi[8][4] = -259.0/6.0 , 650 bi[8][5] = 259.0/15.0 , 651 // -------------------------------------- 652 // 653 // COEFFICIENTS OF bi[9] 654 bi[9][0] = 0.0 , 655 bi[9][1] = 62.0/105.0 , 656 bi[9][2] = -2381.0/525.0 , 657 bi[9][3] = 949.0/75.0 , 658 bi[9][4] = -2636.0/175.0 , 659 bi[9][5] = 1112.0/175.0 , 660 // -------------------------------------- 661 // 662 // COEFFICIENTS OF bi[10] 663 bi[10][0] = 0.0 , 664 bi[10][1] = 43.0/3.0 , 665 bi[10][2] = -1534.0/15.0 , 666 bi[10][3] = 3767.0/15.0 , 667 bi[10][4] = -1264.0/5.0 , 668 bi[10][5] = 448.0/5.0 , 669 // -------------------------------------- 670 // 671 // COEFFICIENTS OF bi[11] 672 bi[11][0] = 0.0 , 673 bi[11][1] = 63.0/5.0 , 674 bi[11][2] = -1494.0/25.0 , 675 bi[11][3] = 2907.0/25.0 , 676 bi[11][4] = -2592.0/25.0 , 677 bi[11][5] = 864.0/25.0 , 678 // -------------------------------------- 679 // 680 // COEFFICIENTS OF bi[12] 681 bi[12][0] = 0.0 , 682 bi[12][1] = -576.0/35.0 , 683 bi[12][2] = 19584.0/175.0 , 684 bi[12][3] = -6336.0/25.0 , 685 bi[12][4] = 41472.0/175.0 , 686 bi[12][5] = -13824.0/175.0 ; 687 // -------------------------------------- 688 689 for(G4int i = 0; i< numberOfVariables; ++i 690 { 691 yIn[i] = yInput[i]; 692 } 693 694 G4double tau0 = tau; 695 696 // Calculating the polynomials (coefficent 697 // 698 for(auto i=1; i<=12; ++i) // i is NOT the 699 { 700 b[i] = 0; 701 tau = 1.0; 702 for(auto j=0; j<=5; ++j) 703 { 704 b[i] += bi[i][j]*tau; 705 tau*=tau0; 706 } 707 } 708 709 // Calculating the interpolation at the fr 710 // the polynomial coefficients and the res 711 // 712 for(G4int i=0; i<numberOfVariables; ++i) / 713 { 714 yOut[i] = yIn[i] + Step*tau0*(b[1]*dydx[ 715 b[4]*ak4[i 716 b[7]*ak7[i 717 b[10]*ak10[i] 718 } 719 } 720