Using dolphin and shelve: on Ubuntu and on Mac OS X

Question

I have run the following script:

from dolfin import *
import shelve

mesh = UnitSquareMesh(3, 3)
V = FunctionSpace(mesh, 'CG', 1)

f = Expression('1 + x[0]*x[1]')
f_proj = project(f, V)

curr_shelf = shelve.open('test_shelf_f')
curr_shelf['dofs of f'] = f_proj.vector().array()
curr_shelf.close()

on Ubuntu, where the shelf gets saved under the filename test_shelf_f (without any extension), and on Mac OS X, where the shelf gets saved under the filename test_shelf_f.db.

Since I developed some code on an Ubuntu machine which now needs to run on a Mac OS X machine, I would like to know how to tell the Mac OS X machine to store the shelf as test_shelf_f.

Any advice will be appreciated.

Answer 1

shelve uses anydbm which in turn selects any of four installed DBM-implementations. This is in my opinion a terrible design, as they are not complete compatible with each other. Naming of the files is one of these compatibility-issues.

To fix it, make sure that the same backend is used. (Check import anydbm; print anydbm._name.)

I would recommend changing from shelve, and using something else instead, e.g. h5py.

Comments

Thank you for the feedback.

After running

import anydbm
print anydbm._name

on both machines, I saw that they're both using the backend dumbdbm. Do you happen to know if there are any further settings that I should check and change so that both machines will store the shelf as test_shelf_f?

Thank you also for recommending h5py - I will look into it as soon as I have the chance.