class cat(*args, copy=False, **kwargs)[source]#

Like np.concatenate(), but takes anything and returns an array. Useful for e.g. appending a single number onto the beginning or end of an array.



arr =, np.ones(3))
arr =[1,2,3]), [4,5], 6)
arr =,4), np.random.rand(2,6), axis=1)
New in version 1.0.0.
New in version 1.1.0: “copy” and keyword arguments.
New in version 2.0.2: removed “copy” argument; changed default axis of 0; arguments passed to np.concatenate()