1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152
|
---
:name: dla_gbrcond
:md5sum: 166b58ae6ab01504cac311045c0152cb
:category: :function
:type: doublereal
:arguments:
- trans:
:type: char
:intent: input
- n:
:type: integer
:intent: input
- kl:
:type: integer
:intent: input
- ku:
:type: integer
:intent: input
- ab:
:type: doublereal
:intent: input
:dims:
- ldab
- n
- ldab:
:type: integer
:intent: input
- afb:
:type: doublereal
:intent: input
:dims:
- ldafb
- n
- ldafb:
:type: integer
:intent: input
- ipiv:
:type: integer
:intent: input
:dims:
- n
- cmode:
:type: integer
:intent: input
- c:
:type: doublereal
:intent: input
:dims:
- n
- info:
:type: integer
:intent: output
- work:
:type: doublereal
:intent: input
:dims:
- 5*n
- iwork:
:type: integer
:intent: input
:dims:
- n
:substitutions: {}
:fortran_help: " DOUBLE PRECISION FUNCTION DLA_GBRCOND( TRANS, N, KL, KU, AB, LDAB, AFB, LDAFB, IPIV, CMODE, C, INFO, WORK, IWORK )\n\n\
* Purpose\n\
* =======\n\
*\n\
* DLA_GBRCOND Estimates the Skeel condition number of op(A) * op2(C)\n\
* where op2 is determined by CMODE as follows\n\
* CMODE = 1 op2(C) = C\n\
* CMODE = 0 op2(C) = I\n\
* CMODE = -1 op2(C) = inv(C)\n\
* The Skeel condition number cond(A) = norminf( |inv(A)||A| )\n\
* is computed by computing scaling factors R such that\n\
* diag(R)*A*op2(C) is row equilibrated and computing the standard\n\
* infinity-norm condition number.\n\
*\n\n\
* Arguments\n\
* =========\n\
*\n\
* TRANS (input) CHARACTER*1\n\
* Specifies the form of the system of equations:\n\
* = 'N': A * X = B (No transpose)\n\
* = 'T': A**T * X = B (Transpose)\n\
* = 'C': A**H * X = B (Conjugate Transpose = Transpose)\n\
*\n\
* N (input) INTEGER\n\
* The number of linear equations, i.e., the order of the\n\
* matrix A. N >= 0.\n\
*\n\
* KL (input) INTEGER\n\
* The number of subdiagonals within the band of A. KL >= 0.\n\
*\n\
* KU (input) INTEGER\n\
* The number of superdiagonals within the band of A. KU >= 0.\n\
*\n\
* AB (input) DOUBLE PRECISION array, dimension (LDAB,N)\n\
* On entry, the matrix A in band storage, in rows 1 to KL+KU+1.\n\
* The j-th column of A is stored in the j-th column of the\n\
* array AB as follows:\n\
* AB(KU+1+i-j,j) = A(i,j) for max(1,j-KU)<=i<=min(N,j+kl)\n\
*\n\
* LDAB (input) INTEGER\n\
* The leading dimension of the array AB. LDAB >= KL+KU+1.\n\
*\n\
* AFB (input) DOUBLE PRECISION array, dimension (LDAFB,N)\n\
* Details of the LU factorization of the band matrix A, as\n\
* computed by DGBTRF. U is stored as an upper triangular\n\
* band matrix with KL+KU superdiagonals in rows 1 to KL+KU+1,\n\
* and the multipliers used during the factorization are stored\n\
* in rows KL+KU+2 to 2*KL+KU+1.\n\
*\n\
* LDAFB (input) INTEGER\n\
* The leading dimension of the array AFB. LDAFB >= 2*KL+KU+1.\n\
*\n\
* IPIV (input) INTEGER array, dimension (N)\n\
* The pivot indices from the factorization A = P*L*U\n\
* as computed by DGBTRF; row i of the matrix was interchanged\n\
* with row IPIV(i).\n\
*\n\
* CMODE (input) INTEGER\n\
* Determines op2(C) in the formula op(A) * op2(C) as follows:\n\
* CMODE = 1 op2(C) = C\n\
* CMODE = 0 op2(C) = I\n\
* CMODE = -1 op2(C) = inv(C)\n\
*\n\
* C (input) DOUBLE PRECISION array, dimension (N)\n\
* The vector C in the formula op(A) * op2(C).\n\
*\n\
* INFO (output) INTEGER\n\
* = 0: Successful exit.\n\
* i > 0: The ith argument is invalid.\n\
*\n\
* WORK (input) DOUBLE PRECISION array, dimension (5*N).\n\
* Workspace.\n\
*\n\
* IWORK (input) INTEGER array, dimension (N).\n\
* Workspace.\n\
*\n\n\
* =====================================================================\n\
*\n\
* .. Local Scalars ..\n LOGICAL NOTRANS\n INTEGER KASE, I, J, KD, KE\n DOUBLE PRECISION AINVNM, TMP\n\
* ..\n\
* .. Local Arrays ..\n INTEGER ISAVE( 3 )\n\
* ..\n\
* .. External Functions ..\n LOGICAL LSAME\n EXTERNAL LSAME\n\
* ..\n\
* .. External Subroutines ..\n EXTERNAL DLACN2, DGBTRS, XERBLA\n\
* ..\n\
* .. Intrinsic Functions ..\n INTRINSIC ABS, MAX\n\
* ..\n"
|