numpy-ndarray

In Pytorch 1.0.0, I found that a tensor variable occupies very small memory. I wonder how it stores so much data. Here's the code. a = np.random.randn(1, 1, 128, 256) b = torch.tensor(a, device=torch.device('cpu')) a_size = sys.getsizeof(a) b_size = sys.getsizeof(b) a_size is 262288. b_size is 72. The answer is in two parts. From the documentation of sys.getsizeof , firstly All built-in objects will return correct results, but this does not have to hold true for third-party extensions as it is implementation specific. so it could be that for tensors __sizeof__ is undefined or defined

Executing import numpy as np t1 = np.arange(1,10) t2 = np.arange(11,20) t3 = np.concatenate((t1,t2),axis=1) results in a Traceback (most recent call last): File "<ipython-input-264-85078aa26398>", line 1, in <module> t3 = np.concatenate((t1,t2),axis=1) IndexError: axis 1 out of bounds [0, 1) why does it report that axis 1 is out of bounds? Your title explains it - a 1d array does not have a 2nd axis! But having said that, on my system as on @Oliver W. s, it does not produce an error In [655]: np.concatenate((t1,t2),axis=1) Out[655]: array([ 1, 2, 3, 4, 5, 6, 7, 8, 9, 11, 12, 13, 14, 15, 16, 17

I have a code written in java (android) that open the camera of the phone and show frames. The below code represents the method in which we can retrieve frames. The project used Chaquopy to interpret python code. @Override public Mat onCameraFrame(CameraBridgeViewBase.CvCameraViewFrame inputFrame) { mRgba = inputFrame.rgba(); Python py = Python.getInstance(); PyObject pym = (PyObject) py.getModule("MyPythonClass").callAttr("call",mRgba); return mRgba; } The python code is used to retrieve the frame (represented by "mRgba" which is a Mat in the java code) for further treatment The problem is to

I have a ndarray like this one: number_of_rows = 3 number_of_columns = 3 a = np.arange(number_of_rows*number_of_columns).reshape(number_of_rows,number_of_columns) a array([[0, 1, 2], [3, 4, 5], [6, 7, 8]]) But I want something like this: array([[0, 100, 101], [3, 102, 103], [6, 7, 8]]) To do that I want to avoid to do it one by one, I rather prefer to do it in arrays or matrices, because later I want to extend the code. Nothe I have change a submatrix of the initial matrix (in mathematical terms, in terms of this example ndarray). In the example the columns considered are [1,2] and the rows [0