Working with multidimensional arrays

This section will give you a brief understanding of multidimensional arrays by going through different matrix operations.

In order to do matrix multiplication in NumPy, you have to use dot() instead of *. Let's see some examples:

In [66]: c = np.ones((4, 4))         c*cOut[66]: array([[ 1., 1., 1., 1.],                [ 1., 1., 1., 1.],                [ 1., 1., 1., 1.],                [ 1., 1., 1., 1.]])In [67]: c.dot(c)Out[67]: array([[ 4., 4., 4., 4.],                [ 4., 4., 4., 4.],                [ 4., 4., 4., 4.],                [ 4., 4., 4., 4.]])

The most important topic in working with multidimensional arrays is stacking, in other words how to merge two arrays. hstack is used for stacking arrays horizontally (column-wise) and vstack is used for stacking arrays vertically (row-wise). You can ...

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