How to get the global eigenvectors from PDSYEVD

[Petros]

Hello,
I was wondering how to transform the local output of eigenvectors Z generated by PDSYEVD:

PDSYEVD( 'V', 'U', N, A, 1, 1, DESCA, EIGENVAL, Z, 1, 1, DESCZ, WORK, LWORK,IWORK, LIWORK, INFO )

into global representation. Ie how to Z(local) -----> Z(global) ?