ndarray.resize: passing the correct value for the refcheck argument

Question

Like many others, my situation is that I have a class which collects a large amount of data, and provides a method to return the data as a numpy array. (Additional data can con

Answer 1

I will use array.array() to do the data collection:

import array
a = array.array("d")
for i in xrange(100):
    a.append(i*2)

Every time when you want to do some calculation with the collected data, convert it to numpy.ndarray by numpy.frombuffer:

b = np.frombuffer(a, dtype=float)
print np.mean(b)

b will share data memory with a, so the convertion is very fast.