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Python: Built-in Functions vs. For & If Loops – 5 Programs Explained

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Python’s built-in functions make coding fast and efficient. But understanding how they work under the hood is crucial to mastering Python. This post shows five Python tasks, each implemented in two ways: Using built-in functions Using for loops and if statements ✅ 1. Sum of a List ✅ Using Built-in Function: numbers = [ 10 , 20 , 30 , 40 ] total = sum (numbers) print ( "Sum:" , total) 🔁 Using For Loop: numbers = [ 10 , 20 , 30 , 40 ] total = 0 for num in numbers: total += num print ( "Sum:" , total) ✅ 2. Find Maximum Value ✅ Using Built-in Function: values = [ 3 , 18 , 7 , 24 , 11 ] maximum = max (values) print ( "Max:" , maximum) 🔁 Using For and If: values = [ 3 , 18 , 7 , 24 , 11 ] maximum = values[ 0 ] for val in values: if val > maximum: maximum = val print ( "Max:" , maximum) ✅ 3. Count Vowels in a String ✅ Using Built-ins: text = "hello world" vowel_count = sum ( 1 for ch in text if ch i...
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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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