text: #include "f2c.h"
  #include "blaswrap.h"
  
  /* Table of constant values */
  
  static integer c__1 = 1;
  
  doublereal zlansp_(char *norm, char *uplo, integer *n, doublecomplex *ap, 
  	doublereal *work)
  {
      /* System generated locals */
      integer i__1, i__2;
      doublereal ret_val, d__1, d__2;
  
      /* Builtin functions */
      double z_abs(doublecomplex *), d_imag(doublecomplex *), sqrt(doublereal);
  
      /* Local variables */
      integer i__, j, k;
      doublereal sum, absa, scale;
      extern logical lsame_(char *, char *);
      doublereal value;
      extern /* Subroutine */ int zlassq_(integer *, doublecomplex *, integer *, 
  	     doublereal *, doublereal *);
  
  
  /*  -- LAPACK auxiliary routine (version 3.1) -- */
  /*     Univ. of Tennessee, Univ. of California Berkeley and NAG Ltd.. */
  /*     November 2006 */
  
  /*     .. Scalar Arguments .. */
  /*     .. */
  /*     .. Array Arguments .. */
  /*     .. */
  
  /*  Purpose */
  /*  ======= */
  
  /*  ZLANSP  returns the value of the one norm,  or the Frobenius norm, or */
  /*  the  infinity norm,  or the  element of  largest absolute value  of a */
  /*  complex symmetric matrix A,  supplied in packed form. */
  
  /*  Description */
  /*  =========== */
  
  /*  ZLANSP returns the value */
  
  /*     ZLANSP = ( max(abs(A(i,j))), NORM = 'M' or 'm' */
  /*              ( */
  /*              ( norm1(A),         NORM = '1', 'O' or 'o' */
  /*              ( */
  /*              ( normI(A),         NORM = 'I' or 'i' */
  /*              ( */
  /*              ( normF(A),         NORM = 'F', 'f', 'E' or 'e' */
  
  /*  where  norm1  denotes the  one norm of a matrix (maximum column sum), */
  /*  normI  denotes the  infinity norm  of a matrix  (maximum row sum) and */
  /*  normF  denotes the  Frobenius norm of a matrix (square root of sum of */
  /*  squares).  Note that  max(abs(A(i,j)))  is not a consistent matrix norm. */
  
  /*  Arguments */
  /*  ========= */
  
  /*  NORM    (input) CHARACTER*1 */
  /*          Specifies the value to be returned in ZLANSP as described */
  /*          above. */
  
  /*  UPLO    (input) CHARACTER*1 */
  /*          Specifies whether the upper or lower triangular part of the */
  /*          symmetric matrix A is supplied. */
  /*          = 'U':  Upper triangular part of A is supplied */
  /*          = 'L':  Lower triangular part of A is supplied */
  
  /*  N       (input) INTEGER */
  /*          The order of the matrix A.  N >= 0.  When N = 0, ZLANSP is */
  /*          set to zero. */
  
  /*  AP      (input) COMPLEX*16 array, dimension (N*(N+1)/2) */
  /*          The upper or lower triangle of the symmetric matrix A, packed */
  /*          columnwise in a linear array.  The j-th column of A is stored */
  /*          in the array AP as follows: */
  /*          if UPLO = 'U', AP(i + (j-1)*j/2) = A(i,j) for 1<=i<=j; */
  /*          if UPLO = 'L', AP(i + (j-1)*(2n-j)/2) = A(i,j) for j<=i<=n. */
  
  /*  WORK    (workspace) DOUBLE PRECISION array, dimension (MAX(1,LWORK)), */
  /*          where LWORK >= N when NORM = 'I' or '1' or 'O'; otherwise, */
  /*          WORK is not referenced. */
  
  /* ===================================================================== */
  
  /*     .. Parameters .. */
  /*     .. */
  /*     .. Local Scalars .. */
  /*     .. */
  /*     .. External Functions .. */
  /*     .. */
  /*     .. External Subroutines .. */
  /*     .. */
  /*     .. Intrinsic Functions .. */
  /*     .. */
  /*     .. Executable Statements .. */
  
      /* Parameter adjustments */
      --work;
      --ap;
  
      /* Function Body */
      if (*n == 0) {
  	value = 0.;
      } else if (lsame_(norm, "M")) {
  
  /*        Find max(abs(A(i,j))). */
  
  	value = 0.;
  	if (lsame_(uplo, "U")) {
  	    k = 1;
  	    i__1 = *n;
  	    for (j = 1; j <= i__1; ++j) {
  		i__2 = k + j - 1;
  		for (i__ = k; i__ <= i__2; ++i__) {
  /* Computing MAX */
  		    d__1 = value, d__2 = z_abs(&ap[i__]);
  		    value = max(d__1,d__2);
  /* L10: */
  		}
  		k += j;
  /* L20: */
  	    }
  	} else {
  	    k = 1;
  	    i__1 = *n;
  	    for (j = 1; j <= i__1; ++j) {
  		i__2 = k + *n - j;
  		for (i__ = k; i__ <= i__2; ++i__) {
  /* Computing MAX */
  		    d__1 = value, d__2 = z_abs(&ap[i__]);
  		    value = max(d__1,d__2);
  /* L30: */
  		}
  		k = k + *n - j + 1;
  /* L40: */
  	    }
  	}
      } else if (lsame_(norm, "I") || lsame_(norm, "O") || *(unsigned char *)norm == '1') {
  
  /*        Find normI(A) ( = norm1(A), since A is symmetric). */
  
  	value = 0.;
  	k = 1;
  	if (lsame_(uplo, "U")) {
  	    i__1 = *n;
  	    for (j = 1; j <= i__1; ++j) {
  		sum = 0.;
  		i__2 = j - 1;
  		for (i__ = 1; i__ <= i__2; ++i__) {
  		    absa = z_abs(&ap[k]);
  		    sum += absa;
  		    work[i__] += absa;
  		    ++k;
  /* L50: */
  		}
  		work[j] = sum + z_abs(&ap[k]);
  		++k;
  /* L60: */
  	    }
  	    i__1 = *n;
  	    for (i__ = 1; i__ <= i__1; ++i__) {
  /* Computing MAX */
  		d__1 = value, d__2 = work[i__];
  		value = max(d__1,d__2);
  /* L70: */
  	    }
  	} else {
  	    i__1 = *n;
  	    for (i__ = 1; i__ <= i__1; ++i__) {
  		work[i__] = 0.;
  /* L80: */
  	    }
  	    i__1 = *n;
  	    for (j = 1; j <= i__1; ++j) {
  		sum = work[j] + z_abs(&ap[k]);
  		++k;
  		i__2 = *n;
  		for (i__ = j + 1; i__ <= i__2; ++i__) {
  		    absa = z_abs(&ap[k]);
  		    sum += absa;
  		    work[i__] += absa;
  		    ++k;
  /* L90: */
  		}
  		value = max(value,sum);
  /* L100: */
  	    }
  	}
      } else if (lsame_(norm, "F") || lsame_(norm, "E")) {
  
  /*        Find normF(A). */
  
  	scale = 0.;
  	sum = 1.;
  	k = 2;
  	if (lsame_(uplo, "U")) {
  	    i__1 = *n;
  	    for (j = 2; j <= i__1; ++j) {
  		i__2 = j - 1;
  		zlassq_(&i__2, &ap[k], &c__1, &scale, &sum);
  		k += j;
  /* L110: */
  	    }
  	} else {
  	    i__1 = *n - 1;
  	    for (j = 1; j <= i__1; ++j) {
  		i__2 = *n - j;
  		zlassq_(&i__2, &ap[k], &c__1, &scale, &sum);
  		k = k + *n - j + 1;
  /* L120: */
  	    }
  	}
  	sum *= 2;
  	k = 1;
  	i__1 = *n;
  	for (i__ = 1; i__ <= i__1; ++i__) {
  	    i__2 = k;
  	    if (ap[i__2].r != 0.) {
  		i__2 = k;
  		absa = (d__1 = ap[i__2].r, abs(d__1));
  		if (scale < absa) {
  /* Computing 2nd power */
  		    d__1 = scale / absa;
  		    sum = sum * (d__1 * d__1) + 1.;
  		    scale = absa;
  		} else {
  /* Computing 2nd power */
  		    d__1 = absa / scale;
  		    sum += d__1 * d__1;
  		}
  	    }
  	    if (d_imag(&ap[k]) != 0.) {
  		absa = (d__1 = d_imag(&ap[k]), abs(d__1));
  		if (scale < absa) {
  /* Computing 2nd power */
  		    d__1 = scale / absa;
  		    sum = sum * (d__1 * d__1) + 1.;
  		    scale = absa;
  		} else {
  /* Computing 2nd power */
  		    d__1 = absa / scale;
  		    sum += d__1 * d__1;
  		}
  	    }
  	    if (lsame_(uplo, "U")) {
  		k = k + i__ + 1;
  	    } else {
  		k = k + *n - i__ + 1;
  	    }
  /* L130: */
  	}
  	value = scale * sqrt(sum);
      }
  
      ret_val = value;
      return ret_val;
  
  /*     End of ZLANSP */
  
  } /* zlansp_ */
  