# Find length of 2D array Python

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How do I find how many rows and columns are in a 2d array?

For example,

``````Input = ([[1, 2], [3, 4], [5, 6]])`
``````

should be displayed as 3 rows and 2 columns.

Like this:

``````numrows = len(input)    # 3 rows in your example
numcols = len(input) # 2 columns in your example
``````

Assuming that all the sublists have the same length (that is, it’s not a jagged array).

You can use `numpy.shape`.

``````import numpy as np
x = np.array([[1, 2],[3, 4],[5, 6]])
``````

Result:

``````>>> x
array([[1, 2],
[3, 4],
[5, 6]])
>>> np.shape(x)
(3, 2)
``````

First value in the tuple is number rows = 3; second value in the tuple is number of columns = 2.

In addition, correct way to count total item number would be:

``````sum(len(x) for x in input)
``````

Assuming input[row][col],

``````    rows = len(input)
cols = map(len, input)  #list of column lengths
``````

You can also use np.size(a,1), 1 here is the axis and this will give you the number of columns

assuming `input[row][col]`

``````rows = len(input)
cols = len(list(zip(*input)))
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