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
|
---
:name: dgetri
:md5sum: c484cb60864677da7365b61f53b577c7
:category: :subroutine
:arguments:
- n:
:type: integer
:intent: input
- a:
:type: doublereal
:intent: input/output
:dims:
- lda
- n
- lda:
:type: integer
:intent: input
- ipiv:
:type: integer
:intent: input
:dims:
- n
- work:
:type: doublereal
:intent: output
:dims:
- MAX(1,lwork)
- lwork:
:type: integer
:intent: input
:option: true
:default: n
- info:
:type: integer
:intent: output
:substitutions: {}
:fortran_help: " SUBROUTINE DGETRI( N, A, LDA, IPIV, WORK, LWORK, INFO )\n\n\
* Purpose\n\
* =======\n\
*\n\
* DGETRI computes the inverse of a matrix using the LU factorization\n\
* computed by DGETRF.\n\
*\n\
* This method inverts U and then computes inv(A) by solving the system\n\
* inv(A)*L = inv(U) for inv(A).\n\
*\n\n\
* Arguments\n\
* =========\n\
*\n\
* N (input) INTEGER\n\
* The order of the matrix A. N >= 0.\n\
*\n\
* A (input/output) DOUBLE PRECISION array, dimension (LDA,N)\n\
* On entry, the factors L and U from the factorization\n\
* A = P*L*U as computed by DGETRF.\n\
* On exit, if INFO = 0, the inverse of the original matrix A.\n\
*\n\
* LDA (input) INTEGER\n\
* The leading dimension of the array A. LDA >= max(1,N).\n\
*\n\
* IPIV (input) INTEGER array, dimension (N)\n\
* The pivot indices from DGETRF; for 1<=i<=N, row i of the\n\
* matrix was interchanged with row IPIV(i).\n\
*\n\
* WORK (workspace/output) DOUBLE PRECISION array, dimension (MAX(1,LWORK))\n\
* On exit, if INFO=0, then WORK(1) returns the optimal LWORK.\n\
*\n\
* LWORK (input) INTEGER\n\
* The dimension of the array WORK. LWORK >= max(1,N).\n\
* For optimal performance LWORK >= N*NB, where NB is\n\
* the optimal blocksize returned by ILAENV.\n\
*\n\
* If LWORK = -1, then a workspace query is assumed; the routine\n\
* only calculates the optimal size of the WORK array, returns\n\
* this value as the first entry of the WORK array, and no error\n\
* message related to LWORK is issued by XERBLA.\n\
*\n\
* INFO (output) INTEGER\n\
* = 0: successful exit\n\
* < 0: if INFO = -i, the i-th argument had an illegal value\n\
* > 0: if INFO = i, U(i,i) is exactly zero; the matrix is\n\
* singular and its inverse could not be computed.\n\
*\n\n\
* =====================================================================\n\
*\n"
|
