NumPy - Array Manipulation

Several routines are available in NumPy package for manipulation of elements in ndarray object. They can be classified into the following types −

Changing Shape

S.No	Shape & Description
1.	reshape Gives a new shape to an array without changing its data
2.	flat A 1-D iterator over the array
3.	flatten Returns a copy of the array collapsed into one dimension
4.	ravel Returns a contiguous flattened array

Transpose Operations

S.No	Operation & Description
1.	transpose Permutes the dimensions of an array
2.	ndarray.T Same as self.transpose()
3.	rollaxis Rolls the specified axis backwards
4.	swapaxes Interchanges the two axes of an array

Changing Dimensions

S.No	Dimension & Description
1.	broadcast Produces an object that mimics broadcasting
2.	broadcast_to Broadcasts an array to a new shape
3.	expand_dims Expands the shape of an array
4.	squeeze Removes single-dimensional entries from the shape of an array

Joining Arrays

S.No	Array & Description
1.	concatenate Joins a sequence of arrays along an existing axis
2.	stack Joins a sequence of arrays along a new axis
3.	hstack Stacks arrays in sequence horizontally (column wise)
4.	vstack Stacks arrays in sequence vertically (row wise)

Splitting Arrays

S.No	Array & Description
1.	split Splits an array into multiple sub-arrays
2.	hsplit Splits an array into multiple sub-arrays horizontally (column-wise)
3.	vsplit Splits an array into multiple sub-arrays vertically (row-wise)

Adding / Removing Elements

S.No	Element & Description
1.	resize Returns a new array with the specified shape
2.	append Appends the values to the end of an array
3.	insert Inserts the values along the given axis before the given indices
4.	delete Returns a new array with sub-arrays along an axis deleted
5.	unique Finds the unique elements of an array