/* nag_zungbr (f08ktc) Example Program.
 *
 * Copyright 2017 Numerical Algorithms Group.
 *
 * Mark 26.1, 2017.
 */

#include <stdio.h>
#include <nag.h>
#include <nag_stdlib.h>
#include <nagf08.h>
#include <nagx04.h>
int main(void)
{
  /* Scalars */
  Integer i, ic, j, m, n, pda, pdc, pdu, pdvt, d_len;
  Integer e_len, tauq_len, taup_len;
  Integer exit_status = 0;
  NagError fail;
  Nag_OrderType order;
  /* Arrays */
  Complex *a = 0, *c = 0, *taup = 0, *tauq = 0, *u = 0, *vt = 0;
  double *d = 0, *e = 0;

#ifdef NAG_COLUMN_MAJOR
#define A(I, J)  a[(J-1)*pda + I - 1]
#define VT(I, J) vt[(J-1)*pdvt + I - 1]
#define U(I, J)  u[(J-1)*pdu + I - 1]
  order = Nag_ColMajor;
#else
#define A(I, J)  a[(I-1)*pda + J - 1]
#define VT(I, J) vt[(I-1)*pdvt + J - 1]
#define U(I, J)  u[(I-1)*pdu + J - 1]
  order = Nag_RowMajor;
#endif

  INIT_FAIL(fail);

  printf("nag_zungbr (f08ktc) Example Program Results\n");

  /* Skip heading in data file */
  scanf("%*[^\n] ");

  for (ic = 1; ic <= 2; ++ic) {
    scanf("%" NAG_IFMT "%" NAG_IFMT "%*[^\n] ", &m, &n);
    d_len = n;
#ifdef NAG_COLUMN_MAJOR
    pda = m;
    pdc = n;
    pdu = m;
    pdvt = m;
    e_len = n - 1;
    tauq_len = n;
    taup_len = n;
#else
    pda = n;
    pdc = n;
    pdu = n;
    pdvt = n;
    e_len = n - 1;
    tauq_len = n;
    taup_len = n;
#endif
    /* Allocate memory */
    if (!(a = NAG_ALLOC(m * n, Complex)) ||
        !(c = NAG_ALLOC(n * n, Complex)) ||
        !(taup = NAG_ALLOC(taup_len, Complex)) ||
        !(tauq = NAG_ALLOC(tauq_len, Complex)) ||
        !(u = NAG_ALLOC(m * n, Complex)) ||
        !(vt = NAG_ALLOC(m * n, Complex)) ||
        !(d = NAG_ALLOC(d_len, double)) || !(e = NAG_ALLOC(e_len, double)))
    {
      printf("Allocation failure\n");
      exit_status = -1;
      goto ENDL;
    }
    /* Read A from data file */
    for (i = 1; i <= m; ++i) {
      for (j = 1; j <= n; ++j)
        scanf(" ( %lf , %lf )", &A(i, j).re, &A(i, j).im);
    }
    scanf("%*[^\n] ");
    /* Reduce A to bidiagonal form */
    /* nag_zgebrd (f08ksc).
     * Unitary reduction of complex general rectangular matrix
     * to bidiagonal form
     */
    nag_zgebrd(order, m, n, a, pda, d, e, tauq, taup, &fail);
    if (fail.code != NE_NOERROR) {
      printf("Error from nag_zgebrd (f08ksc).\n%s\n", fail.message);
      exit_status = 1;
      goto ENDL;
    }
    if (m >= n) {
      /* Copy A to VT and U */
      for (i = 1; i <= n; ++i) {
        for (j = i; j <= n; ++j) {
          VT(i, j).re = A(i, j).re;
          VT(i, j).im = A(i, j).im;
        }
      }
      for (i = 1; i <= m; ++i) {
        for (j = 1; j <= MIN(i, n); ++j) {
          U(i, j).re = A(i, j).re;
          U(i, j).im = A(i, j).im;
        }
      }
      /* Form P^H explicitly, storing the result in VT */
      /* nag_zungbr (f08ktc).
       * Generate unitary transformation matrices from reduction
       * to bidiagonal form determined by nag_zgebrd (f08ksc)
       */
      nag_zungbr(order, Nag_FormP, n, n, m, vt, pdvt, taup, &fail);
      if (fail.code != NE_NOERROR) {
        printf("Error from nag_zungbr (f08ktc).\n%s\n", fail.message);
        exit_status = 1;
        goto ENDL;
      }

      /* Form Q explicitly, storing the result in U */
      /* nag_zungbr (f08ktc), see above. */
      nag_zungbr(order, Nag_FormQ, m, n, n, u, pdu, tauq, &fail);
      if (fail.code != NE_NOERROR) {
        printf("Error from nag_zungbr (f08ktc).\n%s\n", fail.message);
        exit_status = 1;
        goto ENDL;
      }
      /* Compute the SVD of A */
      /* nag_zbdsqr (f08msc).
       * SVD of real bidiagonal matrix reduced from complex
       * general matrix
       */
      nag_zbdsqr(order, Nag_Upper, n, n, m, 0, d, e, vt, pdvt, u,
                 pdu, c, pdc, &fail);
      if (fail.code != NE_NOERROR) {
        printf("Error from nag_zbdsqr (f08msc).\n%s\n", fail.message);
        exit_status = 1;
        goto ENDL;
      }

      /* Print singular values, left & right singular vectors */
      printf("\nExample 1: singular values\n");
      for (i = 1; i <= n; ++i)
        printf("%8.4f%s", d[i - 1], i % 8 == 0 ? "\n" : " ");
      printf("\n\n");
      /* nag_gen_complx_mat_print_comp (x04dbc).
       * Print complex general matrix (comprehensive)
       */
      fflush(stdout);
      nag_gen_complx_mat_print_comp(order, Nag_GeneralMatrix,
                                    Nag_NonUnitDiag, n, n, vt, pdvt,
                                    Nag_BracketForm, "%7.4f",
                                    "Example 1: right singular vectors, "
                                    "by row", Nag_IntegerLabels, 0,
                                    Nag_IntegerLabels, 0, 80, 0, 0, &fail);
      if (fail.code != NE_NOERROR) {
        printf("Error from nag_gen_complx_mat_print_comp (x04dbc)."
               "\n%s\n", fail.message);
        exit_status = 1;
        goto ENDL;
      }
      printf("\n");
      /* nag_gen_complx_mat_print_comp (x04dbc), see above. */
      fflush(stdout);
      nag_gen_complx_mat_print_comp(order, Nag_GeneralMatrix,
                                    Nag_NonUnitDiag, m, n, u, pdu,
                                    Nag_BracketForm, "%7.4f",
                                    "Example 1: left singular vectors, "
                                    "by column", Nag_IntegerLabels, 0,
                                    Nag_IntegerLabels, 0, 80, 0, 0, &fail);
      if (fail.code != NE_NOERROR) {
        printf("Error from nag_gen_complx_mat_print_comp (x04dbc)."
               "\n%s\n", fail.message);
        exit_status = 1;
        goto ENDL;
      }
    }
    else {
      /* Copy A to VT and U */
      for (i = 1; i <= m; ++i) {
        for (j = i; j <= n; ++j) {
          VT(i, j).re = A(i, j).re;
          VT(i, j).im = A(i, j).im;
        }
      }
      for (i = 1; i <= m; ++i) {
        for (j = 1; j <= i; ++j) {
          U(i, j).re = A(i, j).re;
          U(i, j).im = A(i, j).im;
        }
      }
      /* Form P^H explicitly, storing the result in VT */
      /* nag_zungbr (f08ktc), see above. */
      nag_zungbr(order, Nag_FormP, m, n, m, vt, pdvt, taup, &fail);
      if (fail.code != NE_NOERROR) {
        printf("Error from nag_zungbr (f08ktc).\n%s\n", fail.message);
        exit_status = 1;
        goto ENDL;
      }
      /* Form Q explicitly, storing the result in U */
      /* nag_zungbr (f08ktc), see above. */
      nag_zungbr(order, Nag_FormQ, m, m, n, u, pdu, tauq, &fail);
      if (fail.code != NE_NOERROR) {
        printf("Error from nag_zungbr (f08ktc).\n%s\n", fail.message);
        exit_status = 1;
        goto ENDL;
      }
      /* Compute the SVD of A */
      /* nag_zbdsqr (f08msc), see above. */
      nag_zbdsqr(order, Nag_Lower, m, n, m, 0, d, e, vt, pdvt, u,
                 pdu, c, pdc, &fail);
      if (fail.code != NE_NOERROR) {
        printf("Error from nag_zbdsqr (f08msc).\n%s\n", fail.message);
        exit_status = 1;
        goto ENDL;
      }
      /* Print singular values, left & right singular vectors */
      printf("\nExample 2: singular values\n");
      for (i = 1; i <= m; ++i)
        printf("%8.4f%s", d[i - 1], i % 8 == 0 ? "\n" : " ");
      printf("\n\n");
      /* nag_gen_complx_mat_print_comp (x04dbc), see above. */
      fflush(stdout);
      nag_gen_complx_mat_print_comp(order, Nag_GeneralMatrix,
                                    Nag_NonUnitDiag, m, n, vt, pdvt,
                                    Nag_BracketForm, "%7.4f",
                                    "Example 2: right singular vectors, "
                                    "by row", Nag_IntegerLabels, 0,
                                    Nag_IntegerLabels, 0, 80, 0, 0, &fail);
      if (fail.code != NE_NOERROR) {
        printf("Error from nag_gen_complx_mat_print_comp (x04dbc)."
               "\n%s\n", fail.message);
        exit_status = 1;
        goto ENDL;
      }
      printf("\n");
      /* nag_gen_complx_mat_print_comp (x04dbc), see above. */
      fflush(stdout);
      nag_gen_complx_mat_print_comp(order, Nag_GeneralMatrix,
                                    Nag_NonUnitDiag, m, m, u, pdu,
                                    Nag_BracketForm, "%7.4f",
                                    "Example 2: left singular vectors, "
                                    "by column", Nag_IntegerLabels, 0,
                                    Nag_IntegerLabels, 0, 80, 0, 0, &fail);
      if (fail.code != NE_NOERROR) {
        printf("Error from nag_gen_complx_mat_print_comp (x04dbc)."
               "\n%s\n", fail.message);
        exit_status = 1;
        goto ENDL;
      }
    }
  ENDL:
    NAG_FREE(a);
    NAG_FREE(c);
    NAG_FREE(taup);
    NAG_FREE(tauq);
    NAG_FREE(u);
    NAG_FREE(vt);
    NAG_FREE(d);
    NAG_FREE(e);
  }
  NAG_FREE(a);
  NAG_FREE(c);
  NAG_FREE(taup);
  NAG_FREE(tauq);
  NAG_FREE(u);
  NAG_FREE(vt);
  NAG_FREE(d);
  NAG_FREE(e);

  return exit_status;
}