Efficient way to add a singleton dimension to a NumPy vector so that slice assignments work

Question

In NumPy, how can you efficiently make a 1-D object into a 2-D object where the singleton dimension is inferred from the current object (i.e. a list should go to either a 1x

Answer 1

You can always use dstack() to replicate your array:

import numpy

my_list = array([1,2,3,4])
my_list_2D = numpy.dstack((my_list,my_list));