Python provides some in-built data types to stock multiple items in a single variable. A List is one among these built-in data types. However, performing mathematical functions on lists is impossible due to which we need to convert the given lists to matrices or arrays in order to allow the successful performance of certain mathematical functions.
In this article, we will discuss how to convert list to matrix in Python.
Table of Contents
Using the while loop to convert list to matrix in Python.
A matrix can also be described as a list of lists or nested lists.
The process of conversion of the given list to a list of lists can be successfully completed using a simple while loop, along with the use of list slicing and the append() method.
The following code uses the while loop to convert list to matrix in Python.
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lst1 = [1,3,5,7,9,11] m = [] while lst1 != []: matrix.append(lst1[:2]) lst1 = lst1[2:] print(m) |
The above code provides the following output:
Explanation:
- A list containing some elements is defined.
- The
whileloop is used on the list and helps in iterating it till the given list contains no elements. - The list slicing process occurs (list slicing of 2 in this case)
- The append method is used to append the elements into a list of lists
mdefined in the code.
As you can see, a list can easily be converted into a matrix by changing it into a list of lists. However, a better and more reliable way to work on matrices in Python is using the NumPy library, which is described below.
Further reading:
Use the numpy.array() method to convert list to matrix in Python.
NumPy, which is an abbreviation for Numerical Python, is a library that is mainly utilized to deal with matrices and arrays in Python.
The numpy.array() method is utilized in the creation and deletion of arrays in Python. It directly takes a list or a list of lists as an argument and returns a matrix.
To successfully implement this method, we will first need to import the numpy module to the Python code.
The following code uses the numpy.array() method to convert list to matrix in Python.
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import numpy as np lst1 = [1,3,5,7,9,11] m = np.array(lst1) print (m) |
The above code provides the following output:
Using the numpy.asarray() method to convert list to matrix in Python.
Similar to the numpy.array() method mentioned above, the numpy.asarray() method is utilized to convert different data type objects like lists, dictionaries, and more into NumPy matrices. The numpy.asarray() basically calls the numpy.array() method within itself, which makes the syntax of the former function just a simple extension of the latter.
The only difference between the two functions provided by the NumPy module is that in the numpy.asarray() method, the copy flag is set to false by default, while it is true in the case of numpy.array().
The following code uses the numpy.asarray() method to convert list to matrix in Python.
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import numpy as np lst1 = [1,3,5,7,9,11] m = np.asarray(lst1) print (m) |
The above code provides the following output:
Here, the numpy.asarray() does not make a copy of the object and converts the given list straight into a NumPy matrix.
That’s all about how to convert List to matrix in Python.
