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Mastering flat_map in Python with List Comprehension

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Introduction In Python, when working with nested lists or iterables, one common challenge is flattening them into a single list while applying transformations. Many programming languages provide a built-in flatMap function, but Python does not have an explicit flat_map method. However, Python’s powerful list comprehensions offer an elegant way to achieve the same functionality. This article examines implementation behavior using Python’s list comprehensions and other methods. What is flat_map ? Functional programming  flatMap is a combination of map and flatten . It transforms the collection's element and flattens the resulting nested structure into a single sequence. For example, given a list of lists, flat_map applies a function to each sublist and returns a single flattened list. Example in a Functional Programming Language: List(List(1, 2), List(3, 4)).flatMap(x => x.map(_ * 2)) // Output: List(2, 4, 6, 8) Implementing flat_map in Python Using List Comprehension Python’...

19 Top Unix File Scenario Commands

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ETL developers main task is to browse various flat files before they start testing. File browsing in UNIX is tricky. If you know right command to do it you can save a lot of time. These 19 top UNIX files commands useful to use in your project. In UNIX a file normally can have Header, Detail and Trailer. There are scenarios where you need only details without header and Trailer, and need only recent one record, and you need to skip some records from the input files. So for all the File based scenarios, I have given useful UNIX commands.   1). How to print/display the first line of a file?  There are many ways to do this. However the easiest way to display the first line of a file is using the [head] command.  $> head -1 file. Txt If you specify [head -2] then it would print first 2 records of the file.  Another way can be by using [sed] command. [sed] is a very powerful text editor which can be used for various text manipulation purposes like this.  ...