save dictionary python
How to make python save a dictionary to a file. These are small programs that allows you to create a dictionary and then, when running the program, it will create a file that contains the data in the original dictionary.
Given a dictionary such as:
- Comma seperated value file (.csv)
- Json file (.json)
- Text file (.txt)
- Pickle file (.pkl)
save dictionary as csv file
The csv module allows Python programs to write to and read from CSV (comma-separated value) files.
CSV is a common format used for exchanging data between applications. The module provides classes to represent CSV records and fields, and allows outputs to be formatted as CSV files.
In this format every value is separated between a comma, for instance like this:
You can write it to a file with the csv module.
The dictionary file (csv) can be opened in Google Docs or Excel
save dictionary to json file
Today, a JSON file has become more and more common to transfer data in the world. JSON (JavaScript Object Notation) is a lightweight data-interchange format.
JSON is easy for humans to read and write. It is easy for machines to parse and generate.
JSON is a text format that is completely language independent but uses conventions that are familiar to programmers of the C-family of languages, including C, C++, C#, Java, JavaScript, Perl, Python, and many others.
JSON was originally derived from the JavaScript scripting language, but it is not limited to any one programming language.
If you want to save a dictionary to a json file
save dictionary to text file (raw, .txt)
The program below writes a dictionary to an text string. It uses the str() call to convert the dictionary to a text string. While it is easy to write as a text string, this format makes it harder to read the file.
You can save your dictionary to a text file using the code below:
save dictionary to a pickle file (.pkl)
The pickle module may be used to save dictionaries (or other objects) to a file. The module can serialize and deserialize Python objects.
In Python, pickle is a built-in module that implements object serialization. It is both cross-platform and cross language, meaning that it can save and load objects between Python programs running on different operating systems, as well as between Python running on different platforms.
The pickle module is written entirely in Python, and is available in CPython implementations, such as Jython or IronPython. To enable the loading of pickles in other Python modules, pickle supports being executed from the command line.
Как сохранить словарь в файл Python
В Python есть множество способов сохранить словарь в файл. В этой статье мы рассмотрим наиболее популярные из них, а именно: запись в текстовый файл, запись в файл с использованием модуля pickle и запись в файл формата JSON .
Сохранение словаря в текстовый файл
Первый и самый простой способ сохранения словаря в файл — это запись словаря как текста. Python позволяет преобразовать словарь в строку с помощью функции str() , а затем записать эту строку в файл.
Этот код открывает файл с именем my_dict.txt для записи (создавая его, если он не существует), преобразует словарь my_dict в строку и записывает эту строку в файл.
Сохранение словаря в файл с использованием модуля pickle
Модуль pickle в Python используется для сериализации и десериализации объектов. Сериализация — это процесс преобразования объекта в поток байтов для сохранения в файл, передачи по сети или сохранения в базе данных. Десериализация — это обратный процесс, преобразующий поток байтов обратно в объект.
Здесь pickle.dump() используется для сохранения словаря в файл. Обратите внимание, что файл открывается в бинарном режиме для записи.
Загрузка словаря из файла с использованием модуля pickle
Чтобы загрузить сохраненный ранее словарь обратно в память, можно использовать функцию pickle.load() .
Здесь файл открывается в бинарном режиме для чтения, и pickle.load() используется для загрузки словаря из файла.
Сохранение словаря в файл формата JSON
JSON (JavaScript Object Notation) — это легковесный формат обмена данными, который легко читается и пишется. Формат JSON легко использовать в Python с помощью модуля json .
В этом примере json.dump() используется для сохранения словаря в файл JSON.
Загрузка словаря из файла формата JSON
Чтобы загрузить сохраненный ранее словарь из файла JSON, можно использовать функцию json.load() .
Здесь json.load() используется для загрузки словаря из файла JSON.
Заключение
Python предоставляет множество инструментов для сохранения словарей в файлы и загрузки их обратно. Выбор конкретного метода зависит от ваших требований к производительности, совместимости и удобству использования.
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Write Dictionary to file Python (In 5 Ways)
How to write Dictionary to file Python
In this article, we will be solving a problem statement for how to write dictionary to file python. We will be discussing the steps and python methods required to solve this problem.
Table of Contents
What is Dictionary in Python?
Dictionary is one of the data types present in Python. Python dictionary is an unordered collection of items. It is dynamic and mutable in nature. Each item of a dictionary is a key-value pair.
We can define a dictionary by enclosing a list of key-value pairs in curly brackets < >. The keys present in the dictionary must be unique.
We can save dictionary to file in python in various ways. Below we have discussed some of the methods to write dictionary to file in python.
Also Read :
Method 1- Using json.dumps()
Python has an in-built package named as json to support JSON. The json package dumps() method is used to convert a Python object into a JSON string. To know about json package and method read here.
Steps to write dictionary in file using json.dumps:
- import json
- define the dictionary that you want to save in the file
- Open file in write mode
- Write dictionary using json.dumps()
- Close file
Python Code
Output:
mydict.txt file image given below:
Method 2- Using for loop and items()
The dictionary items() method returns an object which contains the list of key-value tuple pair.
- define dictionary
- Open file in write mode
- Loop on the items of the dictionary which we get from dictionary items() method
- Write the key and its corresponding value
- close the file
Using this method, you can write each key-value pair on the new line.
Python Code
Output:
mydict.txt file image given below:
Method 3- using str() to write dictionary to file Python
In this method, we just convert the dictionary into a string and write that string into the file. To convert a dictionary to a string we use the str() function.
Python Code
Output:
mydict.txt file image given below:
Method 4- using keys() method
By using the keys() method of the dictionary we will get all the keys. We will iterate over the keys and write the key and its corresponding value to the file.
Python code:
Output:
mydict.txt file image given below:
Method 5- using pickle.dump() to write dictionary to file Python
The Python Pickle module is used for serializing and de-serializing a Python object. The pickle module converts python objects like lists, dictionaries, etc into a character stream. To know about the Python Pickle module click here.
Since the Pickle module stores data in serialized byte sequence, open the file in wb mode i.e write binary mode and use the pickle module’s dump() method to write dictionary into the file.
Python Code
Note!
When we use the pickle module to write to file, the data is in serialized binary format which is not readable. To read the data again from the file we can use pickle.load() which deserialize the file contents.
Conclusion
In this article, we have seen 5 different ways to write dictionary to file python. We can write dictionary to file by using json.dumps, for loop with dictionary items(), str(), keys() and pickle.dump() method.
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How to save a dictionary to a file?
I have problem with changing a dict value and saving the dict to a text file (the format must be same), I only want to change the member_phone field.
My text file is the following format:
and I split the text file with:
When I try change the member_phone stored in d , the value has changed not flow by the key,
and how to save the dict to a text file with same format?
12 Answers 12
Python has the pickle module just for this kind of thing.
These functions are all that you need for saving and loading almost any object:
In order to save collections of Python there is the shelve module.
Pickle is probably the best option, but in case anyone wonders how to save and load a dictionary to a file using NumPy:
We can also use the json module in the case when dictionaries or some other data can be easily mapped to JSON format.
This solution brings many benefits, eg works for Python 2.x and Python 3.x in an unchanged form and in addition, data saved in JSON format can be easily transferred between many different platforms or programs. This data are also human-readable.