packed storage

[anacondgame]

If A is a symmetric matrix:

1 2 3 1 2 3
A= 2 5 4 Up part = 5 4
3 4 6 6

what is the form for the packed storage array of A?

[1 2 5 3 4 6] (for col)

or

[1 2 3 5 4 6] (for row)


?

[Intel_C_Intel]

You need to provide a bit more context such as for what function. Are you referring to the symmetric linear solvers in LAPACK? For ?potrf, the matrix is stored full. However, for the packed cases, ?pptrf, you have the option of providing either the upper or lower matrix. In either case the data is stored by columns.

Bruce