# How to get the number of dimensions of a matrix using NumPy in Python?

• Last Updated : 03 Mar, 2021

In this article, we will discuss how to get the number of dimensions of a matrix using NumPy. It can be found using the ndim parameter of the ndarray() method.

Syntax: no_of_dimensions = numpy.ndarray.ndim

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Approach:

• Create an n-dimensional matrix using numpy package.
• Use ndim attribute available with numpy array as numpy_array_name.ndim to get the number of dimensions.
• Alternatively, we can use shape attribute to get the size of each dimension and then use len() function for the number of dimensions.
• Use numpy.array() function to convert a list to numpy array and use one of the above two ways to get the number of dimensions.

Example 1:

## Python3

 `import` `numpy as np`` ` ` ` `x ``=` `np.arange(``12``).reshape((``3``, ``4``))``   ` `print``(x.ndim)`

Output:

`2`

Example 2:

## Python3

 `import` `numpy as np`` ` ` ` `# create numpy arrays``# 1-d numpy array``_1darr ``=` `np.arange(``4``)      `` ` `# 2-d numpy array``_2darr ``=` `np.arange(``15``).reshape((``5``, ``3``))     `` ` `# 3-d numpy array``_3darr ``=` `np.arange(``18``).reshape((``3``, ``2``, ``3``))  `` ` `# printing the type of value obtained using ``# attribute 'ndim'``print``(``"Type of value obtained: "``, ``type``(_1darr.ndim))`` ` `# printing the dimensions of each numpy array``print``(``"Dimensions in _1darr are: "``, _1darr.ndim)``print``(``"Dimensions in _2darr are: "``, _2darr.ndim)``print``(``"Dimensions in _3darr are: "``, _3darr.ndim)`` ` `# numpy_arr.shape is the number of elements in``# each dimension numpy_arr.shape returns a tuple``# len() of the returned tuple is also gives number``# of dimensions``print``(``"Dimensions in _3darr are: "``, ``len``(_3darr.shape))`` ` `# Use numpy.array() function to convert a list to``# numpy array``__1darr ``=` `np.array([``5``, ``4``, ``1``, ``3``, ``2``])``__2darr ``=` `np.array([[``5``, ``4``],[``1``,``2``], [``4``,``5``]])``print``(``"Dimensions in __1darr are: "``, __1darr.ndim)``print``(``"Dimensions in __2darr are: "``, __2darr.ndim)`

Output:

```Type of value obtained:  <class 'int'>
Dimensions in _1darr are:  1
Dimensions in _2darr are:  2
Dimensions in _3darr are:  3
Dimensions in _3darr are:  3
Dimensions in __1darr are:  1
Dimensions in __2darr are:  2```

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