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Step-by-Step Guide to Reading Different Files in Python

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 In the world of data science, automation, and general programming, working with files is unavoidable. Whether you’re dealing with CSV reports, JSON APIs, Excel sheets, or text logs, Python provides rich and easy-to-use libraries for reading different file formats. In this guide, we’ll explore how to read different files in Python , with code examples and best practices. 1. Reading Text Files ( .txt ) Text files are the simplest form of files. Python’s built-in open() function handles them effortlessly. Example: # Open and read a text file with open ( "sample.txt" , "r" ) as file: content = file.read() print (content) Explanation: "r" mode means read . with open() automatically closes the file when done. Best Practice: Always use with to handle files to avoid memory leaks. 2. Reading CSV Files ( .csv ) CSV files are widely used for storing tabular data. Python has a built-in csv module and a powerful pandas library. Using cs...
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The best helpful HDFS File System Commands (2 of 4)

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Hadoop+Big data+Jobs, Apply Now
#Top-Selected-HDFS-file-system-commands
CopyFrom Local
Works similarly to the put command, except that the source is restricted to a local file reference.
hdfs dfs -copyFromLocal URI
hdfs dfs -copyFromLocal input/docs/data2.txt hdfs://localhost/user/rosemary/data2.txt

HDFS Commands Part-1of 4

copyToLocal
Works similarly to the get command, except that the destination is restricted to a local file reference.
hdfs dfs -copyToLocal [-ignorecrc] [-crc] URI
hdfs dfs -copyToLocal data2.txt data2.copy.txt

count
Counts the number of directories, files, and bytes under the paths that match the specified file pattern.
hdfs dfs -count [-q]
hdfs dfs -count hdfs://nn1.example.com/file1 hdfs://nn2.example.com/file2

cp
Copies one or more files from a specified source to a specified destination. If you specify multiple sources, the specified destination must be a directory.
hdfs dfs -cp URI [URI …]
hdfs dfs -cp /user/hadoop/file1 /user/hadoop/file2 /user/hadoop/dir

du
Displays the size of the specified file, or the sizes of files and directories that are contained in the specified directory. If you specify the -s option, displays an aggregate summary of file sizes rather than individual file sizes. If you specify the -h option, formats the file sizes in a "human-readable" way.

hdfs dfs -du [-s] [-h] URI [URI …]
hdfs dfs -du /user/hadoop/dir1 /user/hadoo

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