     Next: Selecting a Symmetric Driver Up: Templates and Driver Routines Previous: Templates and Driver Routines

# Symmetric Drivers

There are six drivers for the symmetric eigenvalue problem (and ). They are named in the form of XsdrvY , where the first character X specifies the precision used as follows:
 s single precision d double precision.
The last character Y is a number between 1 and 6 indicating the type of the problem to be solved and the mode to be used. Each number is associated with a unique combination of the bmat and iparam(7) parameters. The parameter which used to select the eigenvalues of interest is controlled by the user, but recommended settings are given in the discussion that follows. Table A.1 lists the problem solved by each double precision driver. The first four drivers are the most commonly used. The last two drivers use two special spectral transformations that may accelerate the convergence for particular problems.

 DRIVER PROBLEM SOLVED dsdrv1 Standard eigenvalue problem (bmat = 'I') in the regular mode (iparam(7) = 1). dsdrv2 Standard eigenvalue problem (bmat = 'I') in a shift-invert mode (iparam(7) = 3). dsdrv3 Generalized eigenvalue problem (bmat = 'G') in the regular inverse mode (iparam(7) = 2). dsdrv4 Generalized eigenvalue problem (bmat = 'G') in a shift-invert mode (iparam(7) = 3). dsdrv5 Generalized eigenvalue problem (bmat = 'G') in the Buckling mode (iparam(7) = 4). dsdrv6 Generalized eigenvalue problem (bmat = 'G') in the Cayley mode (iparam(7) = 5).     Next: Selecting a Symmetric Driver Up: Templates and Driver Routines Previous: Templates and Driver Routines
Chao Yang
11/7/1997