Creating many state vectors and saving them in a file-CodePudding

I want to create m number of matrices, each of which is an n x 1 numpy arrays. Moreover those matrices should have only two nonzero entries in the two rows, all other rows should have 0 as their entries, meaning that matrix number m=1 should have entries m[0,:]=m[1,:]=1, rest elements are 0. And similarly the last matrix m=m should have entries like m[n-1,:]=m[n,:]=1, where rest of the elements in other rows are 0. So for consecutive two matrices, the nonzero elements shift by two rows. And finally, I would like them to be stored into a dictionary or in a file.

What would be a neat way to do this?

CodePudding user response：

Is this what you're looking for?

In [2]: num_rows = 10  # should be divisible by 2

In [3]: np.repeat(np.eye(num_rows // 2), 2, axis=0)
Out[3]:
array([[1., 0., 0., 0., 0.],
       [1., 0., 0., 0., 0.],
       [0., 1., 0., 0., 0.],
       [0., 1., 0., 0., 0.],
       [0., 0., 1., 0., 0.],
       [0., 0., 1., 0., 0.],
       [0., 0., 0., 1., 0.],
       [0., 0., 0., 1., 0.],
       [0., 0., 0., 0., 1.],
       [0., 0., 0., 0., 1.]])

In terms of storage in a file, you can use np.save and np.load.

Note that the default data type for np.eye will be float64. If you expect your values to be small when you begin integrating or whatever you're planning on doing with your state vectors, I'd recommend setting the data type appropriately (like np.uint8 for positive integers < 256 for example).