63 lines
2.4 KiB
Plaintext
63 lines
2.4 KiB
Plaintext
1. Purpose
|
|
-------
|
|
This directory contains example drivers that call subroutines
|
|
[s,d]sband.f, [s,d]nband.f or [c,z]nband.f to solve various eigenvalue
|
|
problems in which matrices have BANDED structure. These drivers illustrate
|
|
how to construct LAPACK-style banded matrices, and how to set various
|
|
ARPACK parameters to solve different problems in different modes. The
|
|
user may modify any one of these drivers, and construct his/her own matrix
|
|
to solve the problem of his/her own interest.
|
|
|
|
2. Naming convention
|
|
-----------------
|
|
The name for each banded solver has the form 'XYband.f', where
|
|
X - is 's' (single precision)
|
|
or 'd' (double precision)
|
|
or 'c' (single precision complex)
|
|
or 'z' (double precision complex)
|
|
|
|
Y - is 's' (symmetric)
|
|
or 'n' (nonsymmetric)
|
|
|
|
The name for each driver has the form 'XYbdrN.f', where
|
|
X - is 's' (single precision)
|
|
or 'd' (double precision)
|
|
or 'c' (single precision complex)
|
|
or 'z' (double precision complex)
|
|
|
|
Y - is 's' (symmetric)
|
|
or 'n' (nonsymmetric)
|
|
|
|
N - is a number between 1 and 6. If
|
|
N = 1, the driver solves a STANDARD eigenvalue problem in
|
|
REGULAR mode.
|
|
N = 2, the driver solves a STANDARD eigenvalue problem in
|
|
SHIFT-INVERT mode.
|
|
N = 3, the driver solves a GENERALIZED eigenvalue problem in
|
|
INVERSE mode.
|
|
N = 4, the driver solves a GENERALIZED eigenvalue problem in
|
|
SHIFT-INVERT mode (using mode 3 of __aupd.)
|
|
These are four commonly used drivers.
|
|
|
|
When N > 4 (only for real matrices), a special mode is used.
|
|
For symmetric problem, if
|
|
N = 5, the driver solves a GENERALIZED eigenvalue problem in
|
|
BUCKLING mode.
|
|
N = 6, the driver solves a GENERALIZED eigenvalue problem in
|
|
CAYLEY mode.
|
|
|
|
For nonsymmetric problem, if
|
|
N = 5, the driver solves a STANDARD eigenvalue problem in
|
|
SHIFT-INVERT mode using mode 4 of [d,s]naupd.f.
|
|
N = 6. the driver solves a GENERALIZED eigenvalue problem
|
|
SHIFT-INVERT mode using mode 4 of [d,s]naupd.f.
|
|
Note: the imaginary part of the shift MUST be nonzero when
|
|
these two drivers are used.
|
|
|
|
3. Usage
|
|
-----
|
|
To run these drivers, you may use the makefile in this
|
|
directory and issue, for example, "make snbdr1". Then
|
|
execute using "snbdr1".
|
|
|