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Questions - mapreduce

Kotlin - How to convert a list of objects into a single one after map operation?

I'm trying to wrap my head around map and reduce operations in Kotlin. At least, I guess it's reduce what I'm trying to do. Let's say that I have a class called Car that takes any number (varargs cons...
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Allan

kotlin

functional-programming

mapreduce

reduce

Votes: 0

Answers: 2

Latest Answer

You can simply use a the spread operator (*) over an array: val mappedCarParts = carParts .map { it.description.toUpperCase() } .map { CarPart(it) } .toTypedArray() val car = Car(*mappedC...
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Some random IT boy

Finding the minimum value of a column using PySpark Map Reduce

I'm looking to find out how I can use the map and reduce functions on a PySpark RDD to determine the smallest value in each of my RDD columns. I understand that the agg function can be used on datafra...
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rossca

apache-spark

pyspark

parallel-processing

mapreduce

rdd

Votes: 0

Answers: 2

Latest Answer

Using the following sample.txt file as an example. A,7.034,0.342 B,3.684,1.043 C,2.963,0.085 Using the following code we can get the minimum value of the val1, and val2 columns Firstly, each line map...
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BoomBoxBoy

How to calculate the minimum maximum and average values for each column in a dataset using MapReduce in pyspark?

Assuming I have a large data set, here is an abbreviated part of it Status,column1,column2,column3,column4 Healthy,4.5044,0.7443,6.34,1.9052 Patient,4.4284,0.9073,5.6433,1.6232 Patient,4.5291,1.0199,6...
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Sucre359

python

pyspark

mapreduce

Votes: 0

Answers: 3

Latest Answer

df.describe() uses native Spark function to run the computation. You can explicitly use select expressions to get the results. from pyspark.sql import functions as F data = [("Healthy", 4.5...
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Nithish

What sort order does couchdb use internally?

I'm unable to find a good answer of how couchdb determines it's sort order in views. I thought it would be in ASCII order or be similar to javascript's sort function which converts everything to UTF-1...
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vividn

sorting

mapreduce

couchdb

Votes: 0

Answers: 1

Latest Answer

This is explained thoroughly in the CouchDB documentation 3.2.2.5. Collation Specification Comparison of strings is done using ICU which implements the Unicode Collation Algorithm, giving a dictionar...
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RamblinRose

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