I want to do drizzling with numpy. It should be trivial, but it's impossible (without a for loop, afaik) instead.
In [2]: a = array([1,1,2,2])
In [3]: b = arange(5)
In [4]: b[a] += 1
In [5]: b
Out[5]: array([0, 2, 3, 3, 4])
In [6]: # but b should really be:
In [7]: b[a] += 1
In [8]: b
Out[8]: array([0, 3, 4, 3, 4])