In python, we have discussed many concepts and conversions. But sometimes, we come to a situation where we need to read a text from a file, write a text from a file, append a text in a file, and save a file in python. In this tutorial, we will be discussing how to save a variable in a file. Show
What are file access modes?Access modes are used to govern the type of operations possible in the opened file. It tells us about how the file will be used once it’s opened. These modes define the location of the file handle in the file. The file handle is just like a cursor, which tells from where the data has to be read or written in the file. We have 6 modes in python:
Many times a user or a python programmer needs to delete or rename a file. To know how to execute these tasks you can read our posts from here:
Here, we will be discussing all the different ways through which we can save a variable in a file in python: 1. Using string concatenation to save a variable in a file in PythonIn this example, we will use open(file, mode) with the file’s pathname as files and mode as ‘w’ to open the file for writing. Then, we will use repr(object) with the object as the variable to convert a variable to a string. After that, we will call the file.write(data) with data
as a string concatenation of three strings, a string containing the variable name and #input text input_dictionary = {"one" : 1, "two" : 2} #open file file = open("Python.txt", "w") #convert variable to string str = repr(input_dictionary) file.write("input_dictionary = " + str + "\n") #close file file.close() f = open('Python.txt', 'r') if f.mode=='r': contents= f.read() Output: Explanation:
2. Using String formatting to save a variable in a file in PythonIn this example, we will be using open(file, mode) with the file’s pathname as a file and modes as ‘w’ to open the file for writing. Then, we will call the file.write(data) with data as the string formats “%s %d” followed by % and a tuple containing a string of the variable name and the variable. At last, we will close the file by using file.close(). Let us look at the example for understanding the concept in detail. #input variable input_dictionary = {"one" : 1, "two" : 2} file = open("Python.txt", "w") file.write("%s = %s\n" %("input_dictionary", input_dictionary)) file.close() f = open('Python.txt', 'r') if f.mode=='r': contents= f.read() Output: Explanation:
3. By importing pickle library to save a variable in a fileIn this example, we will be importing the pickle library. Then, we will be using open(file, mode) with the pathname of a file as a file and modes as ‘w’ to open the file for writing. After that, we will apply the pickle library with the parameters as dict and file as a variable. At last, we will close the file by using file.close(). Let us look at the example for understanding the concept in detail. import pickle input_dictionary = {'one': 1, 'two': 2} file = open('Python.txt', 'w') pickle.dump(input_dictionary, file) file.close() with open('Python.txt', 'rb') as f: dict = pickle.load(f) Output: Explanation:
4. Using numpy library to save a variable in a fileIn this example, we will be importing a numpy library with an alias name as np. Then we will be taking two lists: a and b. Then, we will apply the savetxt() function from the numpy library. Let us look at the example for understanding the concept in detail. import numpy as np a = [1,2,3,4,5] np.savetxt('Python.txt',a) print(open("E:\python.txt").read()) Output: Explanation:
ConclusionIn this tutorial, we have learned about the concept of saving a variable in a file in python. We have seen all the access modes in the file. After that, we have discussed all the ways through which we can save a variable in a file in python. All the ways are explained in detail with the help of examples. You can use any of the functions according to your choice and your requirement in the program. However, if you have any doubts or questions, do let me know in the comment section below. I will try to help you as soon as possible. What is the best way to store data in Python?We're going to consider the following formats to store our data.. Plain-text CSV — a good old friend of a data scientist.. Pickle — a Python's way to serialize things.. MessagePack — it's like JSON but fast and small.. HDF5 —a file format designed to store and organize large amounts of data.. How do you save output data in Python?Use the write() Function to Print Output to a File in Python.. Use the print() Function to Print Output to a File in Python.. Use sys.stdout to Print Output to a File in Python.. Use the contextlib.redirect_stdout() Function to Print Output to a File in Python.. Where does Python store data?Data so received, is stored in computer's main memory (RAM) in the form of various data structures such as, variables and objects until the application is running. Thereafter, memory contents from RAM are erased.
How does Python store data files?Use file. write() to save data to a Python file
Call open(file, mode) with file as the Python file being saved to and mode as "w" to return a writable file object. With file as the result from the previous step, call file. write(data) with data as a string to save it to file .
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