Len () from numpy array in python
If I use len(np.array([[2,3,1,0], [2,3,1,0], [3,2,1,1]]))
I will return 3.
Why are there no arguments for len()
about which axis do I need the length in multidimensional arrays? This is alarming. Is there any alternative?
What is an len
equivalent nested list?
len([[2,3,1,0], [2,3,1,0], [3,2,1,1]])
With a more general concept shape
, the numpy
developers decided to implement __len__
as the first dimension. Python maps len(obj)
to obj.__len__
.
X.shape
It returns a tuple, which has a len
- number of measurements X.ndim
. X.shape[i]
selects the size ith
(direct tuple indexing application).
Easy. Use .shape
.
>>> nparray.shape
(5, 6) #Returns a tuple of array dimensions.
You can move the array if you want to get the length of another dimension.
len(np.array([[2,3,1,0], [2,3,1,0], [3,2,1,1]]).T)