/* blas/source_symm_r.h

 *

 * Copyright (C) 2001, 2007 Brian Gough

 *

 * This program is free software; you can redistribute it and/or modify

 * it under the terms of the GNU General Public License as published by

 * the Free Software Foundation; either version 3 of the License, or (at

 * your option) any later version.

 *

 * This program is distributed in the hope that it will be useful, but

 * WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

 * General Public License for more details.

 *

 * You should have received a copy of the GNU General Public License

 * along with this program; if not, write to the Free Software

 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.

 */

{

  INDEX i, j, k;

  INDEX n1, n2;

  int uplo, side;

  CHECK_ARGS13(SYMM,Order,Side,Uplo,M,N,alpha,A,lda,B,ldb,beta,C,ldc);

  if (alpha == 0.0 && beta == 1.0)

    return;

  if (Order == CblasRowMajor) {

    n1 = M;

    n2 = N;

    uplo = Uplo;

    side = Side;

  } else {

    n1 = N;

    n2 = M;

    uplo = (Uplo == CblasUpper) ? CblasLower : CblasUpper;

    side = (Side == CblasLeft) ? CblasRight : CblasLeft;

  }

  /* form  y := beta*y */

  if (beta == 0.0) {

    for (i = 0; i < n1; i++) {

      for (j = 0; j < n2; j++) {

        C[ldc * i + j] = 0.0;

      }

    }

  } else if (beta != 1.0) {

    for (i = 0; i < n1; i++) {

      for (j = 0; j < n2; j++) {

        C[ldc * i + j] *= beta;

      }

    }

  }

  if (alpha == 0.0)

    return;

  if (side == CblasLeft && uplo == CblasUpper) {

    /* form  C := alpha*A*B + C */

    for (i = 0; i < n1; i++) {

      for (j = 0; j < n2; j++) {

        const BASE temp1 = alpha * B[ldb * i + j];

        BASE temp2 = 0.0;

        C[i * ldc + j] += temp1 * A[i * lda + i];

        for (k = i + 1; k < n1; k++) {

          const BASE Aik = A[i * lda + k];

          C[k * ldc + j] += Aik * temp1;

          temp2 += Aik * B[ldb * k + j];

        }

        C[i * ldc + j] += alpha * temp2;

      }

    }

  } else if (side == CblasLeft && uplo == CblasLower) {

    /* form  C := alpha*A*B + C */

    for (i = 0; i < n1; i++) {

      for (j = 0; j < n2; j++) {

        const BASE temp1 = alpha * B[ldb * i + j];

        BASE temp2 = 0.0;

        for (k = 0; k < i; k++) {

          const BASE Aik = A[i * lda + k];

          C[k * ldc + j] += Aik * temp1;

          temp2 += Aik * B[ldb * k + j];

        }

        C[i * ldc + j] += temp1 * A[i * lda + i] + alpha * temp2;

      }

    }

  } else if (side == CblasRight && uplo == CblasUpper) {

    /* form  C := alpha*B*A + C */

    for (i = 0; i < n1; i++) {

      for (j = 0; j < n2; j++) {

        const BASE temp1 = alpha * B[ldb * i + j];

        BASE temp2 = 0.0;

        C[i * ldc + j] += temp1 * A[j * lda + j];

        for (k = j + 1; k < n2; k++) {

          const BASE Ajk = A[j * lda + k];

          C[i * ldc + k] += temp1 * Ajk;

          temp2 += B[ldb * i + k] * Ajk;

        }

        C[i * ldc + j] += alpha * temp2;

      }

    }

  } else if (side == CblasRight && uplo == CblasLower) {

    /* form  C := alpha*B*A + C */

    for (i = 0; i < n1; i++) {

      for (j = 0; j < n2; j++) {

        const BASE temp1 = alpha * B[ldb * i + j];

        BASE temp2 = 0.0;

        for (k = 0; k < j; k++) {

          const BASE Ajk = A[j * lda + k];

          C[i * ldc + k] += temp1 * Ajk;

          temp2 += B[ldb * i + k] * Ajk;

        }

        C[i * ldc + j] += temp1 * A[j * lda + j] + alpha * temp2;

      }

    }

  } else {

    BLAS_ERROR("unrecognized operation");

  }

}