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Python map() and lambda() Use Cases and Examples

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 In Python, map() and lambda functions are often used together for functional programming. Here are some examples to illustrate how they work. Python map and lambda top use cases 1. Using map() with lambda The map() function applies a given function to all items in an iterable (like a list) and returns a map object (which can be converted to a list). Example: Doubling Numbers numbers = [ 1 , 2 , 3 , 4 , 5 ] doubled = list ( map ( lambda x: x * 2 , numbers)) print (doubled) # Output: [2, 4, 6, 8, 10] 2. Using map() to Convert Data Types Example: Converting Strings to Integers string_numbers = [ "1" , "2" , "3" , "4" , "5" ] integers = list ( map ( lambda x: int (x), string_numbers)) print (integers) # Output: [1, 2, 3, 4, 5] 3. Using map() with Multiple Iterables You can also use map() with more than one iterable. The lambda function can take multiple arguments. Example: Adding Two Lists Element-wise list1 = [ 1 , 2 , 3 ]

The best helpful HDFS File System Commands (2 of 4)

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#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 Disp