wave_write

Castep writes its wavefunctions in a distribution-independent manner. The basic scheme, updated for band-parallelism, is as follows:

• All of the I/O is done by the root-node
• The root node is a kp-master, bnd-master and gv-master
• The root node loops over all nodes that are both bnd- and gv-masters, and receives their data
• Nodes that are both bnd- and gv-masters assemble the gv-distributed data from across their gv-group (i.e. the group of bnd-masters) and send the data to the root node, getting it where necessary from the appropriate node in their bnd-group
• Nodes that are bnd-masters send the appropriate band data to their gv-master, if necessary getting it from the appropriate node in their band-group.
• General nodes send their local data to their band-master

Work completed, tested and working.