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Selecting a Band Storage Driver

Several drivers may be used to solve the same problem. However, one driver may work better or may be easier to modify than the other depending on the nature of the application. The decision of what to use should be based on the type of problem to be solved and the part of the spectrum that is of interest. Typically, regular mode drivers can be used to find extremal eigenvalues and shift-invert drivers are used to find interior eigenvalues or extremal eigenvalues that are clustered.

All of the drivers discussed in the previous sections are available in band form. For more detail on a particular mode, select the driver from the appropriate section above and then use its banded counterpart. For example, if the appropriate general driver is dndrv4 then the corresponding band driver would be dnbdr4. The primary difference between these two is that dnbdr4 has been derived from dndrv4 by modifying it to use band storage and LAPACK band factorization routines.

Chao Yang