### Using zheev subroutine

Posted:

**Mon Aug 20, 2012 7:31 pm**Hi everyone,

I'm using the subroutine zheev to diagonalize a complex hamiltonian matrix.

Here is my problem, if I grow the dimension of my matrix (say dim= dim+100)

I get an error message like this:

On entry to ZHEEV parameter number 8 had an illegal value

If I only use the non-aumented job ( equal to dim ), the task is accomplished

in a good way.

I don't know how to fix this bug, I think it is because one has to initialize the subroutine

doing:

lwork= -1_i4

Call ZHEEV( 'V', 'L', dimen, matrix, dimen, wr, work, lwork, rwork, info ),

but I don't know how to improve the subroutine to do huge dimensional hamiltonian matrix

diagonalizations.

Thanks

Adrian O.

I'm using the subroutine zheev to diagonalize a complex hamiltonian matrix.

Here is my problem, if I grow the dimension of my matrix (say dim= dim+100)

I get an error message like this:

On entry to ZHEEV parameter number 8 had an illegal value

If I only use the non-aumented job ( equal to dim ), the task is accomplished

in a good way.

I don't know how to fix this bug, I think it is because one has to initialize the subroutine

doing:

lwork= -1_i4

Call ZHEEV( 'V', 'L', dimen, matrix, dimen, wr, work, lwork, rwork, info ),

but I don't know how to improve the subroutine to do huge dimensional hamiltonian matrix

diagonalizations.

Thanks

Adrian O.