Questions tagged [Scala] (102)

4
answers

Why learn jvm languages other than Java?

What specific purpose all languages: Kotlin, Scala, Groovy, Clojure and others, if you can write everything in Java? What exactly makes people create/use others? In addition, the syntax or programming style is different, and it sometimes seems that he does not different, just specially modified to so it seemed(like "first n...
francesco_Bechtelar asked March 31st 20 at 20:28
1
answer

How to get the class of the type passed as parameter to the constructor of another class?

Assume we have case class and we want to read its fields. We do socase class Product (name: String, price: Int) val fields = classOf[Product].getDeclaredFields And now we want to transfer the Product type parameter to the constructor a universal class which would read the fields of the passed typeclass SqlModels[T] { // Her...
Nicholas_Yost asked March 31st 20 at 15:22
2
answers

What are the prospects of the scala language?

On the last project where I worked on the buck used the scala language. I like him, I want him to study and find work. Surprised by the lack of discussions in the tag on the toaster. Does this mean that the language is little used in Russia? What is its prospects? And how difficult is it to find a job?
Lionel asked March 31st 20 at 14:28
0
answer

How to add an existing csv file data?

Hello, comrades! Please help to understand. On the SFTP server is a CSV file with the data. In the file there are 4 columns. Is it possible by means of Scala (Spark) to add to this CSV file is additional data at the beginning of the file? For example:| REQUEST_DATE | 2019-02-05 20:00:00 | | USER | Kate | | SEARCH_TYPE | Glo...
harmon_Runolfss asked March 20th 20 at 11:07
3
answers

A project in Scala — what are the difficulties of maintaining code over time?

Hello. The programmer assures to do a project in Scala. Allegedly more simply and quickly resolved the problem. But in many articles about Scala write that to support the projects in that language difficult. Please help to understand, in what complexity? As well as the right decision - a new project to do in Scala. Thank y...
garth.Kreiger48 asked March 18th 20 at 20:27
3
answers

What functional language perspektivnee: Erlang or Scala?

Very popular in recent years functional programming, thanks to many chips, but I have this LAMER. So where to start: Scala or Erlang(Elixir?)? What is promising from us/abroad? What's the difference? And can you teach them without knowledge of Java, for example (in the job they are often along with it)?
demetris.Schulist asked March 17th 20 at 12:43
0
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Working with a DataFrame in Spark?

Hello, comrades! Please help to understand. Assume the DataFrame is stored in the first time the user navigates to the call center.+---------+-------------------+ |USER_NAME| REQUEST_DATE| +---------+-------------------+ | Mark|2018-02-20 00:00:00| | Alex|2018-03-01 00:00:00| | Bob|2018-03-01 00:00:00| | Mark|2018-07-01 00:...
Leola_Sporer asked March 16th 20 at 13:43
0
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How to merge two DataFrame in Spark related?

Hello, colleagues! The Spark Framework and I can't figure out how to merge two DataFrame-and. The first DataFrame stores data about the user requests the service centre. This DataFrame can be called conditionally df1.+-----------+---------------------+ | USER_NAME | REQUEST_DATE | +-----------+---------------------+ | Alex ...
Howell_Murazi asked March 16th 20 at 13:42
3
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Is it true that Scala-is for industrial stat. analysis?

The truth if I said that Scala is predominantly used where required, statistical analysis of large amounts of data?
norbert_King asked March 16th 20 at 13:00
0
answer

How to read multiple parquet files in Spark?

Hello, comrades! Please help to understand with Spark. There is a directory which contains a bunch of parquet files. The name of these files have a common format: "DD-MM-YYYY". For example: '01-10-2018', '02-10-2018', '03-10-2018' , etc. as input parameter, I receive the start date (dateFrom) and an end date (dateTo). The v...
Pinkie.Bartolet asked March 15th 20 at 23:05