/* nag_zpbtrf (f07hrc) Example Program. * * Copyright 2001 Numerical Algorithms Group. * * Mark 7, 2001. */ #include #include #include #include #include int main(void) { /* Scalars */ Integer i, j, k, kd, n, pdab; Integer exit_status = 0; Nag_UploType uplo; NagError fail; Nag_OrderType order; /* Arrays */ char nag_enum_arg[40]; Complex *ab = 0; #ifdef NAG_COLUMN_MAJOR #define AB_UPPER(I, J) ab[(J-1)*pdab + k + I - J - 1] #define AB_LOWER(I, J) ab[(J-1)*pdab + I - J] order = Nag_ColMajor; #else #define AB_UPPER(I, J) ab[(I-1)*pdab + J - I] #define AB_LOWER(I, J) ab[(I-1)*pdab + k + J - I - 1] order = Nag_RowMajor; #endif INIT_FAIL(fail); printf("nag_zpbtrf (f07hrc) Example Program Results\n\n"); /* Skip heading in data file */ scanf("%*[^\n] "); scanf("%ld%ld%*[^\n] ", &n, &kd); pdab = kd + 1; /* Allocate memory */ if (!(ab = NAG_ALLOC((kd+1) * n, Complex))) { printf("Allocation failure\n"); exit_status = -1; goto END; } /* Read A from data file */ scanf(" %39s%*[^\n] ", nag_enum_arg); /* nag_enum_name_to_value (x04nac). * Converts NAG enum member name to value */ uplo = (Nag_UploType) nag_enum_name_to_value(nag_enum_arg); k = kd + 1; if (uplo == Nag_Upper) { for (i = 1; i <= n; ++i) { for (j = i; j <= MIN(i+kd, n); ++j) scanf(" ( %lf , %lf )", &AB_UPPER(i, j).re, &AB_UPPER(i, j).im); } scanf("%*[^\n] "); } else { for (i = 1; i <= n; ++i) { for (j = MAX(1, i-kd); j <= i; ++j) scanf(" ( %lf , %lf )", &AB_LOWER(i, j).re, &AB_LOWER(i, j).im); } scanf("%*[^\n] "); } /* Factorize A */ /* nag_zpbtrf (f07hrc). * Cholesky factorization of complex Hermitian * positive-definite band matrix */ nag_zpbtrf(order, uplo, n, kd, ab, pdab, &fail); if (fail.code != NE_NOERROR) { printf("Error from nag_zpbtrf (f07hrc).\n%s\n", fail.message); exit_status = 1; goto END; } /* Print details of factorization */ if (uplo == Nag_Upper) { /* nag_band_complx_mat_print_comp (x04dfc). * Print complex packed banded matrix (comprehensive) */ fflush(stdout); nag_band_complx_mat_print_comp(order, n, n, 0, kd, ab, pdab, Nag_BracketForm, "%7.4f", "Factor", Nag_IntegerLabels, 0, Nag_IntegerLabels, 0, 80, 0, 0, &fail); } else { /* nag_band_complx_mat_print_comp (x04dfc), see above. */ fflush(stdout); nag_band_complx_mat_print_comp(order, n, n, kd, 0, ab, pdab, Nag_BracketForm, "%7.4f", "Factor", Nag_IntegerLabels, 0, Nag_IntegerLabels, 0, 80, 0, 0, &fail); } if (fail.code != NE_NOERROR) { printf("Error from nag_band_complx_mat_print_comp (x04dfc).\n%s\n", fail.message); exit_status = 1; goto END; } END: NAG_FREE(ab); return exit_status; }