# include # include # include # include # include # include # include using namespace std; # include "tetrahedron_keast_rule.hpp" //****************************************************************************80 void comp_next ( int n, int k, int a[], bool *more, int *h, int *t ) //****************************************************************************80 // // Purpose: // // COMP_NEXT computes the compositions of the integer N into K parts. // // Discussion: // // A composition of the integer N into K parts is an ordered sequence // of K nonnegative integers which sum to N. The compositions (1,2,1) // and (1,1,2) are considered to be distinct. // // The routine computes one composition on each call until there are no more. // For instance, one composition of 6 into 3 parts is // 3+2+1, another would be 6+0+0. // // On the first call to this routine, set MORE = FALSE. The routine // will compute the first element in the sequence of compositions, and // return it, as well as setting MORE = TRUE. If more compositions // are desired, call again, and again. Each time, the routine will // return with a new composition. // // However, when the LAST composition in the sequence is computed // and returned, the routine will reset MORE to FALSE, signaling that // the end of the sequence has been reached. // // This routine originally used a SAVE statement to maintain the // variables H and T. I have decided that it is safer // to pass these variables as arguments, even though the user should // never alter them. This allows this routine to safely shuffle // between several ongoing calculations. // // // There are 28 compositions of 6 into three parts. This routine will // produce those compositions in the following order: // // I A // - --------- // 1 6 0 0 // 2 5 1 0 // 3 4 2 0 // 4 3 3 0 // 5 2 4 0 // 6 1 5 0 // 7 0 6 0 // 8 5 0 1 // 9 4 1 1 // 10 3 2 1 // 11 2 3 1 // 12 1 4 1 // 13 0 5 1 // 14 4 0 2 // 15 3 1 2 // 16 2 2 2 // 17 1 3 2 // 18 0 4 2 // 19 3 0 3 // 20 2 1 3 // 21 1 2 3 // 22 0 3 3 // 23 2 0 4 // 24 1 1 4 // 25 0 2 4 // 26 1 0 5 // 27 0 1 5 // 28 0 0 6 // // Licensing: // // This code is distributed under the GNU LGPL license. // // Modified: // // 02 July 2008 // // Author: // // Original FORTRAN77 version by Albert Nijenhuis, Herbert Wilf. // C++ version by John Burkardt. // // Reference: // // Albert Nijenhuis, Herbert Wilf, // Combinatorial Algorithms for Computers and Calculators, // Second Edition, // Academic Press, 1978, // ISBN: 0-12-519260-6, // LC: QA164.N54. // // Parameters: // // Input, int N, the integer whose compositions are desired. // // Input, int K, the number of parts in the composition. // // Input/output, int A[K], the parts of the composition. // // Input/output, bool *MORE. // Set MORE = FALSE on first call. It will be reset to TRUE on return // with a new composition. Each new call returns another composition until // MORE is set to FALSE when the last composition has been computed // and returned. // // Input/output, int *H, *T, two internal parameters needed for the // computation. The user should allocate space for these in the calling // program, include them in the calling sequence, but never alter them! // { int i; if ( !( *more ) ) { *t = n; *h = 0; a[0] = n; for ( i = 1; i < k; i++ ) { a[i] = 0; } } else { if ( 1 < *t ) { *h = 0; } *h = *h + 1; *t = a[*h-1]; a[*h-1] = 0; a[0] = *t - 1; a[*h] = a[*h] + 1; } *more = ( a[k-1] != n ); return; } //****************************************************************************80 int i4_max ( int i1, int i2 ) //****************************************************************************80 // // Purpose: // // I4_MAX returns the maximum of two I4's. // // Licensing: // // This code is distributed under the GNU LGPL license. // // Modified: // // 13 October 1998 // // Author: // // John Burkardt // // Parameters: // // Input, int I1, I2, are two integers to be compared. // // Output, int I4_MAX, the larger of I1 and I2. // { int value; if ( i2 < i1 ) { value = i1; } else { value = i2; } return value; } //****************************************************************************80 int i4_min ( int i1, int i2 ) //****************************************************************************80 // // Purpose: // // I4_MIN returns the smaller of two I4's. // // Licensing: // // This code is distributed under the GNU LGPL license. // // Modified: // // 13 October 1998 // // Author: // // John Burkardt // // Parameters: // // Input, int I1, I2, two integers to be compared. // // Output, int I4_MIN, the smaller of I1 and I2. // { int value; if ( i1 < i2 ) { value = i1; } else { value = i2; } return value; } //****************************************************************************80 int i4_modp ( int i, int j ) //****************************************************************************80 // // Purpose: // // I4_MODP returns the nonnegative remainder of I4 division. // // Discussion: // // If // NREM = I4_MODP ( I, J ) // NMULT = ( I - NREM ) / J // then // I = J * NMULT + NREM // where NREM is always nonnegative. // // The MOD function computes a result with the same sign as the // quantity being divided. Thus, suppose you had an angle A, // and you wanted to ensure that it was between 0 and 360. // Then mod(A,360) would do, if A was positive, but if A // was negative, your result would be between -360 and 0. // // On the other hand, I4_MODP(A,360) is between 0 and 360, always. // // Example: // // I J MOD I4_MODP I4_MODP Factorization // // 107 50 7 7 107 = 2 * 50 + 7 // 107 -50 7 7 107 = -2 * -50 + 7 // -107 50 -7 43 -107 = -3 * 50 + 43 // -107 -50 -7 43 -107 = 3 * -50 + 43 // // Licensing: // // This code is distributed under the GNU LGPL license. // // Modified: // // 26 May 1999 // // Author: // // John Burkardt // // Parameters: // // Input, int I, the number to be divided. // // Input, int J, the number that divides I. // // Output, int I4_MODP, the nonnegative remainder when I is // divided by J. // { int value; if ( j == 0 ) { cerr << "\n"; cerr << "I4_MODP - Fatal error!\n"; cerr << " I4_MODP ( I, J ) called with J = " << j << "\n"; exit ( 1 ); } value = i % j; if ( value < 0 ) { value = value + abs ( j ); } return value; } //****************************************************************************80* int i4_wrap ( int ival, int ilo, int ihi ) //****************************************************************************80* // // Purpose: // // I4_WRAP forces an I4 to lie between given limits by wrapping. // // Example: // // ILO = 4, IHI = 8 // // I Value // // -2 8 // -1 4 // 0 5 // 1 6 // 2 7 // 3 8 // 4 4 // 5 5 // 6 6 // 7 7 // 8 8 // 9 4 // 10 5 // 11 6 // 12 7 // 13 8 // 14 4 // // Licensing: // // This code is distributed under the GNU LGPL license. // // Modified: // // 19 August 2003 // // Author: // // John Burkardt // // Parameters: // // Input, int IVAL, an integer value. // // Input, int ILO, IHI, the desired bounds for the integer value. // // Output, int I4_WRAP, a "wrapped" version of IVAL. // { int jhi; int jlo; int value; int wide; jlo = i4_min ( ilo, ihi ); jhi = i4_max ( ilo, ihi ); wide = jhi + 1 - jlo; if ( wide == 1 ) { value = jlo; } else { value = jlo + i4_modp ( ival - jlo, wide ); } return value; } //****************************************************************************80 int keast_degree ( int rule ) //****************************************************************************80 // // Purpose: // // KEAST_DEGREE returns the degree of a Keast rule for the triangle. // // Licensing: // // This code is distributed under the GNU LGPL license. // // Modified: // // 26 June 2007 // // Author: // // John Burkardt // // Reference: // // Patrick Keast, // Moderate Degree Tetrahedral Quadrature Formulas, // Computer Methods in Applied Mechanics and Engineering, // Volume 55, Number 3, May 1986, pages 339-348. // // Parameters: // // Input, int RULE, the index of the rule. // // Output, int KEAST_DEGREE, the polynomial degree of exactness of // the rule. // { int degree; if ( rule == 1 ) { degree = 0; } else if ( rule == 2 ) { degree = 1; } else if ( rule == 3 ) { degree = 2; } else if ( rule == 4 ) { degree = 3; } else if ( rule == 5 ) { degree = 4; } else if ( rule == 6 ) { degree = 4; } else if ( rule == 7 ) { degree = 5; } else if ( rule == 8 ) { degree = 6; } else if ( rule == 9 ) { degree = 7; } else if ( rule == 10 ) { degree = 8; } else { degree = -1; cerr << "\n"; cerr << "KEAST_DEGREE - Fatal error!\n"; cerr << " Illegal RULE = " << rule << "\n"; exit ( 1 ); } return degree; } //****************************************************************************80 int keast_order_num ( int rule ) //****************************************************************************80 // // Purpose: // // KEAST_ORDER_NUM returns the order of a Keast rule for the triangle. // // Licensing: // // This code is distributed under the GNU LGPL license. // // Modified: // // 14 December 2006 // // Author: // // John Burkardt // // Reference: // // Patrick Keast, // Moderate Degree Tetrahedral Quadrature Formulas, // Computer Methods in Applied Mechanics and Engineering, // Volume 55, Number 3, May 1986, pages 339-348. // // Parameters: // // Input, int RULE, the index of the rule. // // Output, int KEAST_ORDER_NUM, the order (number of points) of the rule. // { int order; int order_num; int *suborder; int suborder_num; suborder_num = keast_suborder_num ( rule ); suborder = keast_suborder ( rule, suborder_num ); order_num = 0; for ( order = 0; order < suborder_num; order++ ) { order_num = order_num + suborder[order]; } delete [] suborder; return order_num; } //****************************************************************************80 void keast_rule ( int rule, int order_num, double xyz[], double w[] ) //****************************************************************************80 // // Purpose: // // KEAST_RULE returns the points and weights of a Keast rule. // // Licensing: // // This code is distributed under the GNU LGPL license. // // Modified: // // 14 December 2006 // // Author: // // John Burkardt // // Reference: // // Patrick Keast, // Moderate Degree Tetrahedral Quadrature Formulas, // Computer Methods in Applied Mechanics and Engineering, // Volume 55, Number 3, May 1986, pages 339-348. // // Parameters: // // Input, int RULE, the index of the rule. // // Input, int ORDER_NUM, the order (number of points) of the rule. // // Output, double XYZ[3*ORDER_NUM], the points of the rule. // // Output, double W[ORDER_NUM], the weights of the rule. // { int k; int o; int s; int *suborder; int suborder_num; double *suborder_w; double *suborder_xyzz; // // Get the suborder information. // suborder_num = keast_suborder_num ( rule ); suborder_xyzz = new double[4*suborder_num]; suborder_w = new double[suborder_num]; suborder = keast_suborder ( rule, suborder_num ); keast_subrule ( rule, suborder_num, suborder_xyzz, suborder_w ); // // Expand the suborder information to a full order rule. // o = 0; for ( s = 0; s < suborder_num; s++ ) { if ( suborder[s] == 1 ) { xyz[0+o*3] = suborder_xyzz[0+s*4]; xyz[1+o*3] = suborder_xyzz[1+s*4]; xyz[2+o*3] = suborder_xyzz[2+s*4]; w[o] = suborder_w[s]; o = o + 1; } // // For SUBORDER = 4, we list the coordinates of the generator as // // A,B,B,B // // and we generate // // A, B, B = (1,2,3) // B, B, B = (2,3,4) // B, B, A = (3,4,1) // B, A, B = (4,1,2) // else if ( suborder[s] == 4 ) { for ( k = 0; k < 4; k++ ) { xyz[0+o*3] = suborder_xyzz [ i4_wrap(k, 0,3) + s*4 ]; xyz[1+o*3] = suborder_xyzz [ i4_wrap(k+1,0,3) + s*4 ]; xyz[2+o*3] = suborder_xyzz [ i4_wrap(k+2,0,3) + s*4 ]; w[o] = suborder_w[s]; o = o + 1; } } // // For SUBORDER = 6, we list the coordinates of the generator as // // A,A,B,B // // and we generate // // B, A, A = (4,1,2) // A, B, A = (1,4,2) // A, A, B = (1,2,4) // // A, B, B = (1,3,4) // B, A, B = (4,2,3) // B, B, A = (4,3,1) // else if ( suborder[s] == 6 ) { for ( k = 0; k < 3; k++ ) { xyz[0+o*3] = suborder_xyzz [ 0 + s*4 ]; xyz[1+o*3] = suborder_xyzz [ 0 + s*4 ]; xyz[2+o*3] = suborder_xyzz [ 0 + s*4 ]; xyz[k+o*3] = suborder_xyzz [ 2 + s*4 ]; w[o] = suborder_w[s]; o = o + 1; } for ( k = 0; k < 3; k++ ) { xyz[0+o*3] = suborder_xyzz [ 2 + s*4 ]; xyz[1+o*3] = suborder_xyzz [ 2 + s*4 ]; xyz[2+o*3] = suborder_xyzz [ 2 + s*4 ]; xyz[k+o*3] = suborder_xyzz [ 0 + s*4 ]; w[o] = suborder_w[s]; o = o + 1; } } // // For SUBORDER = 12, we list the coordinates of the generator as // // A,A,B,C // // and we generate // // B, A, A // A, B, A // A, A, B // // C, A, A // A, C, A // A, A, C // // A, B, C // B, C, A // C, A, B // A, C, B // C, B, A // B, A, C // else if ( suborder[s] == 12 ) { for ( k = 0; k < 3; k++ ) { xyz[0+o*3] = suborder_xyzz [ 0 + s*4 ]; xyz[1+o*3] = suborder_xyzz [ 0 + s*4 ]; xyz[2+o*3] = suborder_xyzz [ 0 + s*4 ]; xyz[k+o*3] = suborder_xyzz [ 2 + s*4 ]; w[o] = suborder_w[s]; o = o + 1; } for ( k = 0; k < 3; k++ ) { xyz[0+o*3] = suborder_xyzz [ 0 + s*4 ]; xyz[1+o*3] = suborder_xyzz [ 0 + s*4 ]; xyz[2+o*3] = suborder_xyzz [ 0 + s*4 ]; xyz[k+o*3] = suborder_xyzz [ 3 + s*4 ]; w[o] = suborder_w[s]; o = o + 1; } for ( k = 0; k < 3; k++ ) { xyz[0+o*3] = suborder_xyzz [ i4_wrap(k+1,1,3) + s*4 ]; xyz[1+o*3] = suborder_xyzz [ i4_wrap(k+2,1,3) + s*4 ]; xyz[2+o*3] = suborder_xyzz [ i4_wrap(k+3,1,3) + s*4 ]; w[o] = suborder_w[s]; o = o + 1; } for ( k = 0; k < 3; k++ ) { xyz[0+o*3] = suborder_xyzz [ i4_wrap(k+1,1,3) + s*4 ]; xyz[1+o*3] = suborder_xyzz [ i4_wrap(k+3,1,3) + s*4 ]; xyz[2+o*3] = suborder_xyzz [ i4_wrap(k+2,1,3) + s*4 ]; w[o] = suborder_w[s]; o = o + 1; } } else { cerr << "\n"; cerr << "KEAST_RULE - Fatal error!\n;"; cerr << " Illegal SUBORDER(" << s << ") = " << suborder[s] << "\n"; exit ( 1 ); } } delete [] suborder; delete [] suborder_xyzz; delete [] suborder_w; return; } //****************************************************************************80 int keast_rule_num ( void ) //****************************************************************************80 // // Purpose: // // KEAST_RULE_NUM returns the number of Keast rules available. // // Licensing: // // This code is distributed under the GNU LGPL license. // // Modified: // // 26 June 2007 // // Author: // // John Burkardt // // Reference: // // Patrick Keast, // Moderate Degree Tetrahedral Quadrature Formulas, // Computer Methods in Applied Mechanics and Engineering, // Volume 55, Number 3, May 1986, pages 339-348. // // Parameters: // // Output, int KEAST_RULE_NUM, the number of rules available. // { int rule_num; rule_num = 10; return rule_num; } //****************************************************************************80 int *keast_suborder ( int rule, int suborder_num ) //****************************************************************************80 // // Purpose: // // KEAST_SUBORDER returns the suborders for a Keast rule. // // Licensing: // // This code is distributed under the GNU LGPL license. // // Modified: // // 26 June 2007 // // Author: // // John Burkardt // // Reference: // // Patrick Keast, // Moderate Degree Tetrahedral Quadrature Formulas, // Computer Methods in Applied Mechanics and Engineering, // Volume 55, Number 3, May 1986, pages 339-348. // // Parameters: // // Input, int RULE, the index of the rule. // // Input, int SUBORDER_NUM, the number of suborders of the rule. // // Output, int KEAST_SUBORDER[SUBORDER_NUM], the suborders of the rule. // { int *suborder; suborder = new int[suborder_num]; if ( rule == 1 ) { suborder[0] = 1; } else if ( rule == 2 ) { suborder[0] = 4; } else if ( rule == 3 ) { suborder[0] = 1; suborder[1] = 4; } else if ( rule == 4 ) { suborder[0] = 4; suborder[1] = 6; } else if ( rule == 5 ) { suborder[0] = 1; suborder[1] = 4; suborder[2] = 6; } else if ( rule == 6 ) { suborder[0] = 6; suborder[1] = 4; suborder[2] = 4; } else if ( rule == 7 ) { suborder[0] = 1; suborder[1] = 4; suborder[2] = 4; suborder[3] = 6; } else if ( rule == 8 ) { suborder[0] = 4; suborder[1] = 4; suborder[2] = 4; suborder[3] = 12; } else if ( rule == 9 ) { suborder[0] = 1; suborder[1] = 4; suborder[2] = 4; suborder[3] = 4; suborder[4] = 6; suborder[5] = 12; } else if ( rule == 10 ) { suborder[0] = 1; suborder[1] = 4; suborder[2] = 4; suborder[3] = 6; suborder[4] = 6; suborder[5] = 12; suborder[6] = 12; } else { cerr << "\n"; cerr << "KEAST_SUBORDER - Fatal error!\n"; cerr << " Illegal RULE = " << rule << "\n"; exit ( 1 ); } return suborder; } //****************************************************************************80 int keast_suborder_num ( int rule ) //****************************************************************************80 // // Purpose: // // KEAST_SUBORDER_NUM returns the number of suborders for a Keast rule. // // Licensing: // // This code is distributed under the GNU LGPL license. // // Modified: // // 26 June 2007 // // Author: // // John Burkardt // // Reference: // // Patrick Keast, // Moderate Degree Tetrahedral Quadrature Formulas, // Computer Methods in Applied Mechanics and Engineering, // Volume 55, Number 3, May 1986, pages 339-348. // // Parameters: // // Input, int RULE, the index of the rule. // // Output, int KEAST_SUBORDER_NUM, the number of suborders of the rule. // { int suborder_num; if ( rule == 1 ) { suborder_num = 1; } else if ( rule == 2 ) { suborder_num = 1; } else if ( rule == 3 ) { suborder_num = 2; } else if ( rule == 4 ) { suborder_num = 2; } else if ( rule == 5 ) { suborder_num = 3; } else if ( rule == 6 ) { suborder_num = 3; } else if ( rule == 7 ) { suborder_num = 4; } else if ( rule == 8 ) { suborder_num = 4; } else if ( rule == 9 ) { suborder_num = 6; } else if ( rule == 10 ) { suborder_num = 7; } else { suborder_num = -1; cerr << "\n"; cerr << "KEAST_SUBORDER_NUM - Fatal error!\n"; cerr << " Illegal RULE = " << rule << "\n"; exit ( 1 ); } return suborder_num; } //****************************************************************************80 void keast_subrule ( int rule, int suborder_num, double suborder_xyzz[], double suborder_w[] ) //****************************************************************************80 // // Purpose: // // KEAST_SUBRULE returns a compressed Keast rule. // // Licensing: // // This code is distributed under the GNU LGPL license. // // Modified: // // 26 June 2007 // // Author: // // John Burkardt // // Reference: // // Patrick Keast, // Moderate Degree Tetrahedral Quadrature Formulas, // Computer Methods in Applied Mechanics and Engineering, // Volume 55, Number 3, May 1986, pages 339-348. // // Parameters: // // Input, int RULE, the index of the rule. // // Input, int SUBORDER_NUM, the number of suborders of the rule. // // Output, double SUBORDER_XYZZ[4*SUBORDER_NUM], // the barycentric coordinates of the abscissas. // // Output, double SUBORDER_W[SUBORDER_NUM], the suborder weights. // { int s; if ( rule == 1 ) { keast_subrule_01 ( suborder_num, suborder_xyzz, suborder_w ); } else if ( rule == 2 ) { keast_subrule_02 ( suborder_num, suborder_xyzz, suborder_w ); } else if ( rule == 3 ) { keast_subrule_03 ( suborder_num, suborder_xyzz, suborder_w ); } else if ( rule == 4 ) { keast_subrule_04 ( suborder_num, suborder_xyzz, suborder_w ); } else if ( rule == 5 ) { keast_subrule_05 ( suborder_num, suborder_xyzz, suborder_w ); } else if ( rule == 6 ) { keast_subrule_06 ( suborder_num, suborder_xyzz, suborder_w ); } else if ( rule == 7 ) { keast_subrule_07 ( suborder_num, suborder_xyzz, suborder_w ); } else if ( rule == 8 ) { keast_subrule_08 ( suborder_num, suborder_xyzz, suborder_w ); } else if ( rule == 9 ) { keast_subrule_09 ( suborder_num, suborder_xyzz, suborder_w ); } else if ( rule == 10 ) { keast_subrule_10 ( suborder_num, suborder_xyzz, suborder_w ); } else { cerr << "\n"; cerr << "KEAST_SUBRULE - Fatal error!\n"; cerr << " Illegal RULE = " << rule << "\n"; exit ( 1 ); } // // Renormalize the weights so they sum to 1. // for ( s = 0; s < suborder_num; s++ ) { suborder_w[s] = 6.0 * suborder_w[s]; } return; } //****************************************************************************80 void keast_subrule_01 ( int suborder_num, double suborder_xyzz[], double suborder_w[] ) //****************************************************************************80 // // Purpose: // // KEAST_SUBRULE_01 returns a compressed Keast rule 1. // // Licensing: // // This code is distributed under the GNU LGPL license. // // Modified: // // 14 December 2006 // // Author: // // John Burkardt // // Reference: // // Patrick Keast, // Moderate Degree Tetrahedral Quadrature Formulas, // Computer Methods in Applied Mechanics and Engineering, // Volume 55, Number 3, May 1986, pages 339-348.. // // Parameters: // // Input, int SUBORDER_NUM, the number of suborders of the rule. // // Output, double SUBORDER_XYZZ[4*SUBORDER_NUM], // the barycentric coordinates of the abscissas. // // Output, double SUBORDER_W[SUBORDER_NUM], the suborder weights. // { int s; double suborder_xyzz_rule_01[4*1] = { 0.250000000000000000, 0.250000000000000000, 0.250000000000000000, 0.250000000000000000 }; double suborder_w_rule_01[1] = { 0.166666666666666667 }; for ( s = 0; s < suborder_num; s++ ) { suborder_xyzz[0+s*4] = suborder_xyzz_rule_01[0+s*4]; suborder_xyzz[1+s*4] = suborder_xyzz_rule_01[1+s*4]; suborder_xyzz[2+s*4] = suborder_xyzz_rule_01[2+s*4]; suborder_xyzz[3+s*4] = suborder_xyzz_rule_01[3+s*4]; } for ( s = 0; s < suborder_num; s++ ) { suborder_w[s] = suborder_w_rule_01[s]; } return; } //****************************************************************************80 void keast_subrule_02 ( int suborder_num, double suborder_xyzz[], double suborder_w[] ) //****************************************************************************80 // // Purpose: // // KEAST_SUBRULE_02 returns a compressed Keast rule 2. // // Licensing: // // This code is distributed under the GNU LGPL license. // // Modified: // // 14 December 2006 // // Author: // // John Burkardt // // Reference: // // Patrick Keast, // Moderate Degree Tetrahedral Quadrature Formulas, // Computer Methods in Applied Mechanics and Engineering, // Volume 55, Number 3, May 1986, pages 339-348. // // Parameters: // // Input, int SUBORDER_NUM, the number of suborders of the rule. // // Output, double SUBORDER_XYZZ[4*SUBORDER_NUM], // the barycentric coordinates of the abscissas. // // Output, double SUBORDER_W[SUBORDER_NUM], the suborder weights. // { int s; double suborder_xyzz_rule_02[4*1] = { 0.585410196624968500, 0.138196601125010500, 0.138196601125010500, 0.138196601125010500 }; double suborder_w_rule_02[1] = { 0.0416666666666666667 }; for ( s = 0; s < suborder_num; s++ ) { suborder_xyzz[0+s*4] = suborder_xyzz_rule_02[0+s*4]; suborder_xyzz[1+s*4] = suborder_xyzz_rule_02[1+s*4]; suborder_xyzz[2+s*4] = suborder_xyzz_rule_02[2+s*4]; suborder_xyzz[3+s*4] = suborder_xyzz_rule_02[3+s*4]; } for ( s = 0; s < suborder_num; s++ ) { suborder_w[s] = suborder_w_rule_02[s]; } return; } //****************************************************************************80 void keast_subrule_03 ( int suborder_num, double suborder_xyzz[], double suborder_w[] ) //****************************************************************************80 // // Purpose: // // KEAST_SUBRULE_03 returns a compressed Keast rule 3. // // Licensing: // // This code is distributed under the GNU LGPL license. // // Modified: // // 26 June 2007 // // Author: // // John Burkardt // // Reference: // // Patrick Keast, // Moderate Degree Tetrahedral Quadrature Formulas, // Computer Methods in Applied Mechanics and Engineering, // Volume 55, Number 3, May 1986, pages 339-348. // // Parameters: // // Input, int SUBORDER_NUM, the number of suborders of the rule. // // Output, double SUBORDER_XYZZ[4*SUBORDER_NUM], // the barycentric coordinates of the abscissas. // // Output, double SUBORDER_W[SUBORDER_NUM], the suborder weights. // { int s; double suborder_xyzz_rule_03[4*5] = { 0.250000000000000000, 0.250000000000000000, 0.250000000000000000, 0.250000000000000000, 0.500000000000000000, 0.166666666666666667, 0.166666666666666667, 0.166666666666666667 }; double suborder_w_rule_03[5] = { -0.133333333333333333, 0.075000000000000000 }; for ( s = 0; s < suborder_num; s++ ) { suborder_xyzz[0+s*4] = suborder_xyzz_rule_03[0+s*4]; suborder_xyzz[1+s*4] = suborder_xyzz_rule_03[1+s*4]; suborder_xyzz[2+s*4] = suborder_xyzz_rule_03[2+s*4]; suborder_xyzz[3+s*4] = suborder_xyzz_rule_03[3+s*4]; } for ( s = 0; s < suborder_num; s++ ) { suborder_w[s] = suborder_w_rule_03[s]; } return; } //****************************************************************************80 void keast_subrule_04 ( int suborder_num, double suborder_xyzz[], double suborder_w[] ) //****************************************************************************80 // // Purpose: // // KEAST_SUBRULE_04 returns a compressed Keast rule 4. // // Licensing: // // This code is distributed under the GNU LGPL license. // // Modified: // // 14 December 2006 // // Author: // // John Burkardt // // Reference: // // Patrick Keast, // Moderate Degree Tetrahedral Quadrature Formulas, // Computer Methods in Applied Mechanics and Engineering, // Volume 55, Number 3, May 1986, pages 339-348. // // Parameters: // // Input, int SUBORDER_NUM, the number of suborders of the rule. // // Output, double SUBORDER_XYZZ[4*SUBORDER_NUM], // the barycentric coordinates of the abscissas. // // Output, double SUBORDER_W[SUBORDER_NUM], the suborder weights. // { int s; double suborder_xyzz_rule_04[4*2] = { 0.568430584196844400, 0.143856471934385200, 0.143856471934385200, 0.143856471934385200, 0.500000000000000000, 0.500000000000000000, 0.000000000000000000, 0.000000000000000000 }; double suborder_w_rule_04[2] = { 0.0362941783134009000, 0.00358165890217718333 }; for ( s = 0; s < suborder_num; s++ ) { suborder_xyzz[0+s*4] = suborder_xyzz_rule_04[0+s*4]; suborder_xyzz[1+s*4] = suborder_xyzz_rule_04[1+s*4]; suborder_xyzz[2+s*4] = suborder_xyzz_rule_04[2+s*4]; suborder_xyzz[3+s*4] = suborder_xyzz_rule_04[3+s*4]; } for ( s = 0; s < suborder_num; s++ ) { suborder_w[s] = suborder_w_rule_04[s]; } return; } //****************************************************************************80 void keast_subrule_05 ( int suborder_num, double suborder_xyzz[], double suborder_w[] ) //****************************************************************************80 // // Purpose: // // KEAST_SUBRULE_05 returns a compressed Keast rule 5. // // Licensing: // // This code is distributed under the GNU LGPL license. // // Modified: // // 11 December 2006 // // Author: // // John Burkardt // // Reference: // // Patrick Keast, // Moderate Degree Tetrahedral Quadrature Formulas, // Computer Methods in Applied Mechanics and Engineering, // Volume 55, Number 3, May 1986, pages 339-348. // // Parameters: // // Input, int SUBORDER_NUM, the number of suborders of the rule. // // Output, double SUBORDER_XYZZ[4*SUBORDER_NUM], // the barycentric coordinates of the abscissas. // // Output, double SUBORDER_W[SUBORDER_NUM], the suborder weights. // { int s; double suborder_xyzz_rule_05[4*3] = { 0.250000000000000000, 0.250000000000000000, 0.250000000000000000, 0.250000000000000000, 0.785714285714285714, 0.0714285714285714285, 0.0714285714285714285, 0.0714285714285714285, 0.399403576166799219, 0.399403576166799219, 0.100596423833200785, 0.100596423833200785 }; double suborder_w_rule_05[3] = { -0.0131555555555555556, 0.00762222222222222222, 0.0248888888888888889 }; for ( s = 0; s < suborder_num; s++ ) { suborder_xyzz[0+s*4] = suborder_xyzz_rule_05[0+s*4]; suborder_xyzz[1+s*4] = suborder_xyzz_rule_05[1+s*4]; suborder_xyzz[2+s*4] = suborder_xyzz_rule_05[2+s*4]; suborder_xyzz[3+s*4] = suborder_xyzz_rule_05[3+s*4]; } for ( s = 0; s < suborder_num; s++ ) { suborder_w[s] = suborder_w_rule_05[s]; } return; } //****************************************************************************80 void keast_subrule_06 ( int suborder_num, double suborder_xyzz[], double suborder_w[] ) //****************************************************************************80 // // Purpose: // // KEAST_SUBRULE_06 returns a compressed Keast rule 6. // // Licensing: // // This code is distributed under the GNU LGPL license. // // Modified: // // 26 June 2007 // // Author: // // John Burkardt // // Reference: // // Patrick Keast, // Moderate Degree Tetrahedral Quadrature Formulas, // Computer Methods in Applied Mechanics and Engineering, // Volume 55, Number 3, May 1986, pages 339-348. // // Parameters: // // Input, int SUBORDER_NUM, the number of suborders of the rule. // // Output, double SUBORDER_XYZZ[4*SUBORDER_NUM], // the barycentric coordinates of the abscissas. // // Output, double SUBORDER_W[SUBORDER_NUM], the suborder weights. // { int s; double suborder_xyzz_rule_06[4*3] = { 0.500000000000000000, 0.500000000000000000, 0.000000000000000000, 0.000000000000000000, 0.698419704324386603, 0.100526765225204467, 0.100526765225204467, 0.100526765225204467, 0.0568813795204234229, 0.314372873493192195, 0.314372873493192195, 0.314372873493192195 }; double suborder_w_rule_06[3] = { 0.00317460317460317450, 0.0147649707904967828, 0.0221397911142651221 }; for ( s = 0; s < suborder_num; s++ ) { suborder_xyzz[0+s*4] = suborder_xyzz_rule_06[0+s*4]; suborder_xyzz[1+s*4] = suborder_xyzz_rule_06[1+s*4]; suborder_xyzz[2+s*4] = suborder_xyzz_rule_06[2+s*4]; suborder_xyzz[3+s*4] = suborder_xyzz_rule_06[3+s*4]; } for ( s = 0; s < suborder_num; s++ ) { suborder_w[s] = suborder_w_rule_06[s]; } return; } //****************************************************************************80 void keast_subrule_07 ( int suborder_num, double suborder_xyzz[], double suborder_w[] ) //****************************************************************************80 // // Purpose: // // KEAST_SUBRULE_07 returns a compressed Keast rule 7. // // Licensing: // // This code is distributed under the GNU LGPL license. // // Modified: // // 11 December 2006 // // Author: // // John Burkardt // // Reference: // // Patrick Keast, // Moderate Degree Tetrahedral Quadrature Formulas, // Computer Methods in Applied Mechanics and Engineering, // Volume 55, Number 3, May 1986, pages 339-348. // // Parameters: // // Input, int SUBORDER_NUM, the number of suborders of the rule. // // Output, double SUBORDER_XYZZ[4*SUBORDER_NUM], // the barycentric coordinates of the abscissas. // // Output, double SUBORDER_W[SUBORDER_NUM], the suborder weights. // { int s; double suborder_xyzz_rule_07[4*4] = { 0.250000000000000000, 0.250000000000000000, 0.250000000000000000, 0.250000000000000000, 0.00000000000000000, 0.333333333333333333, 0.333333333333333333, 0.333333333333333333, 0.727272727272727273, 0.0909090909090909091, 0.0909090909090909091, 0.0909090909090909091, 0.0665501535736642813, 0.0665501535736642813, 0.433449846426335728, 0.433449846426335728 }; double suborder_w_rule_07[4] = { 0.0302836780970891856, 0.00602678571428571597, 0.0116452490860289742, 0.0109491415613864534 }; for ( s = 0; s < suborder_num; s++ ) { suborder_xyzz[0+s*4] = suborder_xyzz_rule_07[0+s*4]; suborder_xyzz[1+s*4] = suborder_xyzz_rule_07[1+s*4]; suborder_xyzz[2+s*4] = suborder_xyzz_rule_07[2+s*4]; suborder_xyzz[3+s*4] = suborder_xyzz_rule_07[3+s*4]; } for ( s = 0; s < suborder_num; s++ ) { suborder_w[s] = suborder_w_rule_07[s]; } return; } //****************************************************************************80 void keast_subrule_08 ( int suborder_num, double suborder_xyzz[], double suborder_w[] ) //****************************************************************************80 // // Purpose: // // KEAST_SUBRULE_08 returns a compressed Keast rule 8. // // Licensing: // // This code is distributed under the GNU LGPL license. // // Modified: // // 11 December 2006 // // Author: // // John Burkardt // // Reference: // // Patrick Keast, // Moderate Degree Tetrahedral Quadrature Formulas, // Computer Methods in Applied Mechanics and Engineering, // Volume 55, Number 3, May 1986, pages 339-348. // // Parameters: // // Input, int SUBORDER_NUM, the number of suborders of the rule. // // Output, double SUBORDER_XYZZ[4*SUBORDER_NUM], // the barycentric coordinates of the abscissas. // // Output, double SUBORDER_W[SUBORDER_NUM], the suborder weights. // { int s; double suborder_xyzz_rule_08[4*4] = { 0.356191386222544953, 0.214602871259151684, 0.214602871259151684, 0.214602871259151684, 0.877978124396165982, 0.0406739585346113397, 0.0406739585346113397, 0.0406739585346113397, 0.0329863295731730594, 0.322337890142275646, 0.322337890142275646, 0.322337890142275646, 0.0636610018750175299, 0.0636610018750175299, 0.269672331458315867, 0.603005664791649076 }; double suborder_w_rule_08[4] = { 0.00665379170969464506, 0.00167953517588677620, 0.00922619692394239843, 0.00803571428571428248 }; for ( s = 0; s < suborder_num; s++ ) { suborder_xyzz[0+s*4] = suborder_xyzz_rule_08[0+s*4]; suborder_xyzz[1+s*4] = suborder_xyzz_rule_08[1+s*4]; suborder_xyzz[2+s*4] = suborder_xyzz_rule_08[2+s*4]; suborder_xyzz[3+s*4] = suborder_xyzz_rule_08[3+s*4]; } for ( s = 0; s < suborder_num; s++ ) { suborder_w[s] = suborder_w_rule_08[s]; } return; } //****************************************************************************80 void keast_subrule_09 ( int suborder_num, double suborder_xyzz[], double suborder_w[] ) //****************************************************************************80 // // Purpose: // // KEAST_SUBRULE_08 returns a compressed Keast rule 8. // // Licensing: // // This code is distributed under the GNU LGPL license. // // Modified: // // 11 December 2006 // // Author: // // John Burkardt // // Reference: // // Patrick Keast, // Moderate Degree Tetrahedral Quadrature Formulas, // Computer Methods in Applied Mechanics and Engineering, // Volume 55, Number 3, May 1986, pages 339-348. // // Parameters: // // Input, int SUBORDER_NUM, the number of suborders of the rule. // // Output, double SUBORDER_XYZZ[4*SUBORDER_NUM], // the barycentric coordinates of the abscissas. // // Output, double SUBORDER_W[SUBORDER_NUM], the suborder weights. // { int s; double suborder_xyzz_rule_09[4*6] = { 0.250000000000000000, 0.250000000000000000, 0.250000000000000000, 0.250000000000000000, 0.765360423009044044, 0.0782131923303186549, 0.0782131923303186549, 0.0782131923303186549, 0.634470350008286765, 0.121843216663904411, 0.121843216663904411, 0.121843216663904411, 0.00238250666073834549, 0.332539164446420554, 0.332539164446420554, 0.332539164446420554, 0.500000000000000000, 0.500000000000000000, 0.00000000000000000, 0.00000000000000000, 0.100000000000000000, 0.100000000000000000, 0.200000000000000000, 0.600000000000000000 }; double suborder_w_rule_09[6] = { 0.0182642234661087939, 0.0105999415244141609, -0.0625177401143299494, 0.00489142526307353653, 0.000970017636684296702, 0.0275573192239850917 }; for ( s = 0; s < suborder_num; s++ ) { suborder_xyzz[0+s*4] = suborder_xyzz_rule_09[0+s*4]; suborder_xyzz[1+s*4] = suborder_xyzz_rule_09[1+s*4]; suborder_xyzz[2+s*4] = suborder_xyzz_rule_09[2+s*4]; suborder_xyzz[3+s*4] = suborder_xyzz_rule_09[3+s*4]; } for ( s = 0; s < suborder_num; s++ ) { suborder_w[s] = suborder_w_rule_09[s]; } return; } //****************************************************************************80 void keast_subrule_10 ( int suborder_num, double suborder_xyzz[], double suborder_w[] ) //****************************************************************************80 // // Purpose: // // KEAST_SUBRULE_10 returns a compressed Keast rule 10. // // Licensing: // // This code is distributed under the GNU LGPL license. // // Modified: // // 11 December 2006 // // Author: // // John Burkardt // // Reference: // // Patrick Keast, // Moderate Degree Tetrahedral Quadrature Formulas, // Computer Methods in Applied Mechanics and Engineering, // Volume 55, Number 3, May 1986, pages 339-348. // // Parameters: // // Input, int SUBORDER_NUM, the number of suborders of the rule. // // Output, double SUBORDER_XYZZ[4*SUBORDER_NUM], // the barycentric coordinates of the abscissas. // // Output, double SUBORDER_W[SUBORDER_NUM], the suborder weights. // { int s; double suborder_xyzz_rule_10[4*7] = { 0.250000000000000000, 0.250000000000000000, 0.250000000000000000, 0.250000000000000000, 0.617587190300082967, 0.127470936566639015, 0.127470936566639015, 0.127470936566639015, 0.903763508822103123, 0.0320788303926322960, 0.0320788303926322960, 0.0320788303926322960, 0.0497770956432810185, 0.0497770956432810185, 0.450222904356718978, 0.450222904356718978, 0.183730447398549945, 0.183730447398549945, 0.316269552601450060, 0.316269552601450060, 0.231901089397150906, 0.231901089397150906, 0.0229177878448171174, 0.513280033360881072, 0.0379700484718286102, 0.0379700484718286102, 0.730313427807538396, 0.193746475248804382 }; double suborder_w_rule_10[7] = { -0.0393270066412926145, 0.00408131605934270525, 0.000658086773304341943, 0.00438425882512284693, 0.0138300638425098166, 0.00424043742468372453, 0.00223873973961420164 }; for ( s = 0; s < suborder_num; s++ ) { suborder_xyzz[0+s*4] = suborder_xyzz_rule_10[0+s*4]; suborder_xyzz[1+s*4] = suborder_xyzz_rule_10[1+s*4]; suborder_xyzz[2+s*4] = suborder_xyzz_rule_10[2+s*4]; suborder_xyzz[3+s*4] = suborder_xyzz_rule_10[3+s*4]; } for ( s = 0; s < suborder_num; s++ ) { suborder_w[s] = suborder_w_rule_10[s]; } return; } //****************************************************************************80 double *monomial_value ( int dim_num, int point_num, double x[], int expon[] ) //****************************************************************************80 // // Purpose: // // MONOMIAL_VALUE evaluates a monomial. // // Discussion: // // This routine evaluates a monomial of the form // // product ( 1 <= dim <= dim_num ) x(dim)^expon(dim) // // where the exponents are nonnegative integers. Note that // if the combination 0^0 is encountered, it should be treated // as 1. // // Licensing: // // This code is distributed under the GNU LGPL license. // // Modified: // // 05 May 2007 // // Author: // // John Burkardt // // Parameters: // // Input, int DIM_NUM, the spatial dimension. // // Input, int POINT_NUM, the number of points at which the // monomial is to be evaluated. // // Input, double X[DIM_NUM*POINT_NUM], the point coordinates. // // Input, int EXPON[DIM_NUM], the exponents. // // Output, double MONOMIAL_VALUE[POINT_NUM], the value of the monomial. // { int dim; int point; double *value; value = new double[point_num]; for ( point = 0; point < point_num; point++ ) { value[point] = 1.0; } for ( dim = 0; dim < dim_num; dim++ ) { if ( 0 != expon[dim] ) { for ( point = 0; point < point_num; point++ ) { value[point] = value[point] * pow ( x[dim+point*dim_num], expon[dim] ); } } } return value; } //****************************************************************************80 double r8_huge ( void ) //****************************************************************************80 // // Purpose: // // R8_HUGE returns a "huge" R8. // // Discussion: // // HUGE_VAL is the largest representable legal double precision number, // and is usually defined in math.h, or sometimes in stdlib.h. // // Licensing: // // This code is distributed under the GNU LGPL license. // // Modified: // // 31 August 2004 // // Author: // // John Burkardt // // Parameters: // // Output, double R8_HUGE, a "huge" R8 value. // { return HUGE_VAL; } //****************************************************************************80 int r8_nint ( double x ) //****************************************************************************80 // // Purpose: // // R8_NINT returns the nearest integer to an R8. // // Example: // // X Value // // 1.3 1 // 1.4 1 // 1.5 1 or 2 // 1.6 2 // 0.0 0 // -0.7 -1 // -1.1 -1 // -1.6 -2 // // Licensing: // // This code is distributed under the GNU LGPL license. // // Modified: // // 26 August 2004 // // Author: // // John Burkardt // // Parameters: // // Input, double X, the value. // // Output, int R8_NINT, the nearest integer to X. // { int s; int value; if ( x < 0.0 ) { s = -1; } else { s = 1; } value = s * ( int ) ( fabs ( x ) + 0.5 ); return value; } //****************************************************************************80 double r8mat_det_4d ( double a[] ) //****************************************************************************80 // // Purpose: // // R8MAT_DET_4D computes the determinant of a 4 by 4 R8MAT. // // Discussion: // // An R8MAT is a doubly dimensioned array of double precision values, which // may be stored as a vector in column-major order. // // Licensing: // // This code is distributed under the GNU LGPL license. // // Modified: // // 10 September 2003 // // Author: // // John Burkardt // // Parameters: // // Input, double A[4*4], the matrix whose determinant is desired. // // Output, double R8MAT_DET_4D, the determinant of the matrix. // { double det; det = a[0+0*4] * ( a[1+1*4] * ( a[2+2*4] * a[3+3*4] - a[2+3*4] * a[3+2*4] ) - a[1+2*4] * ( a[2+1*4] * a[3+3*4] - a[2+3*4] * a[3+1*4] ) + a[1+3*4] * ( a[2+1*4] * a[3+2*4] - a[2+2*4] * a[3+1*4] ) ) - a[0+1*4] * ( a[1+0*4] * ( a[2+2*4] * a[3+3*4] - a[2+3*4] * a[3+2*4] ) - a[1+2*4] * ( a[2+0*4] * a[3+3*4] - a[2+3*4] * a[3+0*4] ) + a[1+3*4] * ( a[2+0*4] * a[3+2*4] - a[2+2*4] * a[3+0*4] ) ) + a[0+2*4] * ( a[1+0*4] * ( a[2+1*4] * a[3+3*4] - a[2+3*4] * a[3+1*4] ) - a[1+1*4] * ( a[2+0*4] * a[3+3*4] - a[2+3*4] * a[3+0*4] ) + a[1+3*4] * ( a[2+0*4] * a[3+1*4] - a[2+1*4] * a[3+0*4] ) ) - a[0+3*4] * ( a[1+0*4] * ( a[2+1*4] * a[3+2*4] - a[2+2*4] * a[3+1*4] ) - a[1+1*4] * ( a[2+0*4] * a[3+2*4] - a[2+2*4] * a[3+0*4] ) + a[1+2*4] * ( a[2+0*4] * a[3+1*4] - a[2+1*4] * a[3+0*4] ) ); return det; } //****************************************************************************80 double r8vec_dot ( int n, double a1[], double a2[] ) //****************************************************************************80 // // Purpose: // // R8VEC_DOT computes the dot product of a pair of R8VEC's. // // Licensing: // // This code is distributed under the GNU LGPL license. // // Modified: // // 03 July 2005 // // Author: // // John Burkardt // // Parameters: // // Input, int N, the number of entries in the vectors. // // Input, double A1[N], A2[N], the two vectors to be considered. // // Output, double R8VEC_DOT, the dot product of the vectors. // { int i; double value; value = 0.0; for ( i = 0; i < n; i++ ) { value = value + a1[i] * a2[i]; } return value; } //****************************************************************************80 int s_len_trim ( char *s ) //****************************************************************************80 // // Purpose: // // S_LEN_TRIM returns the length of a string to the last nonblank. // // Licensing: // // This code is distributed under the GNU LGPL license. // // Modified: // // 26 April 2003 // // Author: // // John Burkardt // // Parameters: // // Input, char *S, a pointer to a string. // // Output, int S_LEN_TRIM, the length of the string to the last nonblank. // If S_LEN_TRIM is 0, then the string is entirely blank. // { int n; char *t; n = strlen ( s ); t = s + strlen ( s ) - 1; while ( 0 < n ) { if ( *t != ' ' ) { return n; } t--; n--; } return n; } //****************************************************************************80 void tetrahedron_reference_to_physical ( double t[], int n, double ref[], double phy[] ) //****************************************************************************80 // // Purpose: // // TETRAHEDRON_REFERENCE_TO_PHYSICAL maps reference points to physical points. // // Discussion: // // Given the vertices of an order 4 physical tetrahedron and a point // (R,S,T) in the reference triangle, the routine computes the value // of the corresponding image point (X,Y,Z) in physical space. // // This routine will also be correct for an order 10 tetrahedron, // if the mapping between reference and physical space // is linear. This implies, in particular, that the sides of the // image tetrahedron are straight, the faces are flat, and // the "midside" nodes in the physical tetrahedron are // halfway along the edges of the physical tetrahedron. // // Licensing: // // This code is distributed under the GNU LGPL license. // // Modified: // // 06 December 2006 // // Author: // // John Burkardt // // Parameters: // // Input, double T[3*4], the coordinates of the vertices. // The vertices are assumed to be the images of (0,0,0), (1,0,0), // (0,1,0) and (0,0,1) respectively. // // Input, int N, the number of points to transform. // // Input, double REF[3*N], points in the reference tetrahedron // // Output, double PHY[3*N], corresponding points in the // physical tetrahedron. // { int i; int j; for ( i = 0; i < 3; i++ ) { for ( j = 0; j < n; j++ ) { phy[i+j*3] = t[i+0*3] * ( 1.0 - ref[0+j*3] - ref[1+j*3] - ref[2+j*3] ) + t[i+1*3] * + ref[0+j*3] + t[i+2*3] * + ref[1+j*3] + t[i+3*3] * + ref[2+j*3]; } } return; } //****************************************************************************80 double tetrahedron_volume ( double tetra[3*4] ) //****************************************************************************80 // // Purpose: // // TETRAHEDRON_VOLUME computes the volume of a tetrahedron in 3D. // // Licensing: // // This code is distributed under the GNU LGPL license. // // Modified: // // 06 August 2005 // // Author: // // John Burkardt // // Parameters: // // Input, double TETRA[3*4], the vertices of the tetrahedron. // // Output, double TETRAHEDRON_VOLUME, the volume of the tetrahedron. // { double a[4*4]; int i; int j; double volume; for ( i = 0; i < 3; i++ ) { for ( j = 0; j < 4; j++ ) { a[i+j*4] = tetra[i+j*3]; } } i = 3; for ( j = 0; j < 4; j++ ) { a[i+j*4] = 1.0; } volume = fabs ( r8mat_det_4d ( a ) ) / 6.0; return volume; } //****************************************************************************80 void timestamp ( void ) //****************************************************************************80 // // Purpose: // // TIMESTAMP prints the current YMDHMS date as a time stamp. // // Example: // // 31 May 2001 09:45:54 AM // // Licensing: // // This code is distributed under the GNU LGPL license. // // Modified: // // 24 September 2003 // // Author: // // John Burkardt // // Parameters: // // None // { # define TIME_SIZE 40 static char time_buffer[TIME_SIZE]; const struct tm *tm; time_t now; now = time ( NULL ); tm = localtime ( &now ); strftime ( time_buffer, TIME_SIZE, "%d %B %Y %I:%M:%S %p", tm ); cout << time_buffer << "\n"; return; # undef TIME_SIZE }