How to reshape array in Numpy?

Let’s see how to use numpy reshape method to reshape an array in Numpy Python module.

Reshaping an array

Suppose you would like to reshape a one-dimensional array into a four-dimensional one.

import numpy as np

my_array = np.arange(24)

reshaped_array = my_array.reshape(4, 6)
print("my array")
print(my_array)
print("reshaped array")
print(reshaped_array)

I used the np.reshape function. The first element is the new number of dimensions.

In other words, the first argument will be the number of rows and the second one will be the number of columns.

The `reshape` method was able to reshape the one-dimensional array into a four-dimensional array with 4 rows and 6 columns.

Other parameters of Numpy reshape method

The `reshape` method in Numpy has several other parameters that can be used to customize the output.

• `order`: The order in which the elements of the array are reshaped. The default value is `C`.
  • `C`: The elements are reshaped in column-major order. This is the default order for Numpy arrays.
  • `F`: The elements are reshaped in row-major order. This is the order that is used by most other programming languages.
• `axes`: A list of integers that specifies the new dimensions of the array. The length of the list must be equal to the number of dimensions in the output array.
• `copy`: If set to True, the output array will be a copy of the input array. The default value is False.

When to use Numpy reshape method?

The `reshape` method in Numpy can be used in a variety of situations, but it is most commonly used when you need to change the shape of an array. For example, you might use the `reshape` method to:

* Change the number of dimensions of an array.
* Change the size of each dimension of an array.
* Align the array with the shape of another array.
* Prepare an array for plotting or saving to a file.

Key Takeaways

• The `reshape` method in Numpy can be used to change the shape of an array.
• The `reshape` method takes two parameters: the new number of dimensions and the new shape of the array.
• The `reshape` method can be used to change the number of dimensions of an array, the size of each dimension of an array, or to align the array with the shape of another array.

FAQ

• **What is the difference between `reshape` and `resize`?**
• reshape method changes the shape of an array without changing the data in the array. resize method changes the shape of an array and may also change the data in the array.
• **What is the order of the elements in a reshaped array?**
• The order of the elements in a reshaped array is determined by the `order` parameter of the `reshape` method. The default value of `order` is `C`, which means that the elements are ordered in column-major order.
• **What happens if I try to reshape an array to a shape that is not compatible with the data in the array?**
• If you try to reshape an array to a shape that is not compatible with the data in the array, the `reshape` method will raise an error.