merging loop produces and giving a name
Question: 
    import numpy as np
    A=([ 3.,1.],  [1.,4.],  [1.,0.], [2., 1.])
    for i in A:
       y=i*1
       print y
    

This python loop produces four lists as shown:

    
    
    [3.0, 1.0]
    [1.0, 4.0]
    [1.0, 0.0]
    [2.0, 1.0]
    

But it should be as shown below, other words it should be a matrix. How can it
be like that? My second question is how can I give a name to this matrix ?

For example A, B or x something like this

    
    
      ([[3.0, 1.0]
        [1.0, 4.0]
        [1.0, 0.0]
        [2.0, 1.0]])
    

and

    
    
    A=([[3.0, 1.0]
        [1.0, 4.0]
        [1.0, 0.0]
        [2.0, 1.0]])
    


Answer: When you write this line, you simply have a tuple, which has 4 `list`
elements.

    
    
    A = ([ 3.,1.],  [1.,4.],  [1.,0.], [2., 1.])
    

If you want to make a `numpy.matrix`, then you can use that to initialize `A`

    
    
    import numpy as np
    A = np.matrix([[ 3.,1.],  [1.,4.],  [1.,0.], [2., 1.]])
    

So `A` is now

    
    
    >>> A
    matrix([[ 3.,  1.],
            [ 1.,  4.],
            [ 1.,  0.],
            [ 2.,  1.]])
    

