- Published on
Understanding the attributes of NumPy arrays and their versatility.
- Authors
- Name
- Kagema Njoroge
- @reecejames934
Numpy is at the backbone of numerical computing in Python.
Below are the attributes of a Numpy array.
- ndarray.ndim
Gives the number of dimensions of the array as an integer value
array = np.array([1, 2, 3])
array.ndim # Returns 1
array2 = np.array([[2, 3, 4], [2, 3, 4]])
array2.ndim # Returns 2
- ndarray.shape
Gives the sequence of integers indicating the size of the array for each dimension
array = np.array([1, 2, 3])
array.shape # Returns (3,)
array2 = np.array([[3, 4, 5], [6, 7, 8]])
array2.shape # Returns (2, 3)
- ndarray.size
It returns the total number of elements in the array
arr = np.array([3, 4, 6])
np.size # Returns 3
arr2 = np.array([[3, 5, 7], [8, 90, 10]])
arr2.size # Returns 6
- ndarray.dtype
Returns the data type of the elements in the array. All elements in the array are of same data type. Common data types areint32
,int64
float32
,float64
,U32
array = np.array([10, 20, 30])
array.dtype # Returns int64
array2 = np.array(["Python", "Pytorch", "Maths", "Statistics", "AI"])
array2.dtype # Returns <U10>
- ndarray.itemsize
It specifies the size in bytes of each element in the array. Data type int32 and float32 means each element of the array occupies 32 bits in memory. 8 bits form a byte. Thus, an array of elements of type int32 has itemsize 32/8 = 4 bytes.
arr = np.array([3, 4, 5])
arr.itemsize # Returns 8 - the dtype of array is int64, thus each item has 64 / 8 = 8 bytes