Python Numpy append array without flattening
The fastest way would be vstack
data = np.vstack((get_data() for i in range(datalen)))vstack requires a tuple/iterable
data = np.vstack((data1, data2, data3))or you can do this by appending with axis=0
data = np.empty(shape=(0, 3))data = np.append(data, datai.reshape((-1, 3)), axis=0) # -1 will make the rows automatic
Solution 1 using list comprehensions:
data = []datalen = 4datai = range(1,4)data = [list(datai) for _ in range(datalen)]print (data)Output
[[1, 2, 3], [1, 2, 3], [1, 2, 3], [1, 2, 3]]Solution 2 (just a bit lengthy)
data = []datalen = 4for i in range(datalen): datai = range(1,4) data.append(list(datai))print (data) with the same output as above. In the second method you can also just simply use data.append(list(range(1,4))). You can choose if you want to convert datai to list or not. If you want the final output as an array, you can just use np.array()