Welcome to OStack Knowledge Sharing Community for programmer and developer-Open, Learning and Share
Login
Remember
Register
Ask
Q&A
All Activity
Hot!
Unanswered
Tags
Users
Ask a Question
Ask a Question
Categories
All categories
Topic[话题] (13)
Life[生活] (4)
Technique[技术] (2.1m)
Idea[创意] (3)
Jobs[工作] (2)
Others[杂七杂八] (18)
Code Example[编程示例] (0)
Recent questions tagged scala
0
votes
2.2k
views
1
answer
scala - flatMap with Shapeless yield FlatMapper not found
I'm trying to define some structure like this case class Transformer[From, To]( name: String, get: ... .flatMap(new filterName(names)) See Question&Answers more detail:os...
asked
Oct 24, 2021
in
Technique[技术]
by
深蓝
(
71.8m
points)
scala
0
votes
1.9k
views
1
answer
scala - Parametric type + function requires a string as second parameter?
class TestClass[T](val x: T) { def +(other: TestClass[T]) = x + other.x } this definition gives me ... parameter and use addition in Scala?? See Question&Answers more detail:os...
asked
Oct 24, 2021
in
Technique[技术]
by
深蓝
(
71.8m
points)
scala
0
votes
2.4k
views
1
answer
scala - How to hide scrollbars in the JavaFX WebView
I'm trying to remove the scrollbars in a javafx webview. Search on forums, the suggestion is to make them invisible ... in Scala code. Thanks! S See Question&Answers more detail:os...
asked
Oct 24, 2021
in
Technique[技术]
by
深蓝
(
71.8m
points)
scala
0
votes
2.5k
views
1
answer
scala - Spark join produces wrong results
Presenting here before possibly filing a bug. I'm using Spark 1.6.0. This is a simplified version of the ... behaviour? If expected, why? See Question&Answers more detail:os...
asked
Oct 24, 2021
in
Technique[技术]
by
深蓝
(
71.8m
points)
scala
0
votes
2.1k
views
1
answer
scala reflection
I want to create a hashmap to store parameters names and their values. The parameters however are with different ... better way to store pair? See Question&Answers more detail:os...
asked
Oct 24, 2021
in
Technique[技术]
by
深蓝
(
71.8m
points)
scala
0
votes
2.0k
views
1
answer
scala - Error when trying to write to hdfs: Server IPC version 9 cannot communicate with client version 4
I am trying a write a file to hdfs using scala and I keep getting the following error Caused by: org.apache.hadoop. ... I do to make this work? See Question&Answers more detail:os...
asked
Oct 24, 2021
in
Technique[技术]
by
深蓝
(
71.8m
points)
scala
0
votes
2.2k
views
1
answer
scala - Add additional directory to clean task in SBT build
I have a SBT build where the tests create temporary files into a directory called temp. How can I tell SBT to ... when I call the clean task? See Question&Answers more detail:os...
asked
Oct 24, 2021
in
Technique[技术]
by
深蓝
(
71.8m
points)
scala
0
votes
2.3k
views
1
answer
scala - Why can't i define a variable recursively in a code block?
Why can't i define a variable recursively in a code block? scala> { | val test: Stream[Int] = 1 #:: ... a compilation error in a code block. See Question&Answers more detail:os...
asked
Oct 24, 2021
in
Technique[技术]
by
深蓝
(
71.8m
points)
scala
0
votes
2.7k
views
1
answer
scala - Spark DataFrame equivalent to Pandas Dataframe `.iloc()` method?
Is there a way to reference Spark DataFrame columns by position using an integer? Analogous Pandas DataFrame operation ... at column position 0 See Question&Answers more detail:os...
asked
Oct 24, 2021
in
Technique[技术]
by
深蓝
(
71.8m
points)
scala
0
votes
1.9k
views
1
answer
scala - Difference in flattening an Option[List[Int]] in 2.9.1 and 2.10 nightly
I get different behaviour in 2.9.1 and 2.10 nightly -- what changed? Welcome to Scala version 2.9.1.final (OpenJDK ... => List(x, -x)) flatten See Question&Answers more detail:os...
asked
Oct 24, 2021
in
Technique[技术]
by
深蓝
(
71.8m
points)
scala
0
votes
2.4k
views
1
answer
scala - sbt-assembly : including test classes
As part of sbt-assembly I want to include both src and test class files in jar. Sbt-assembly includes only ... test classes also in same jar? See Question&Answers more detail:os...
asked
Oct 24, 2021
in
Technique[技术]
by
深蓝
(
71.8m
points)
scala
0
votes
2.4k
views
1
answer
scala - How to concatenate two streams in Apache Flink
E.g. i want to compose stream of 1, 2, 3 and 4, 5 in single one, so result should be: 1, 2, ... with datetime included, but with same result. See Question&Answers more detail:os...
asked
Oct 24, 2021
in
Technique[技术]
by
深蓝
(
71.8m
points)
scala
0
votes
2.1k
views
1
answer
scala - Non-integer ids in Spark MLlib ALS
I'd like to use val ratings = data.map(_.split(',') match { case Array(user,item,rate) => Rating(user. ... How can i do to solve the problem? See Question&Answers more detail:os...
asked
Oct 24, 2021
in
Technique[技术]
by
深蓝
(
71.8m
points)
scala
0
votes
2.2k
views
1
answer
scala - How to create encoder for Option type constructor, e.g. Option[Int]?
Is it possible to use Option[_] member in a case class used with Dataset API? eg. Option[Int] I tried ... class outside of the Main function. See Question&Answers more detail:os...
asked
Oct 24, 2021
in
Technique[技术]
by
深蓝
(
71.8m
points)
scala
0
votes
2.1k
views
1
answer
scala - Why can I not flatMap a List[Option] using underscore?
Why can I write val flat: List[Int] = List(Some(1), Some(2)).flatMap(i => i) But not val flat: List[Int] = List(Some(1), Some(2)).flatMap(_) See Question&Answers more detail:os...
asked
Oct 24, 2021
in
Technique[技术]
by
深蓝
(
71.8m
points)
scala
0
votes
1.9k
views
1
answer
scala - Spark Dataset aggregation similar to RDD aggregate(zero)(accum, combiner)
RDD has a very useful method aggregate that allows to accumulate with some zero value and combine that across partitions. ... ? Thanks a lot! VK See Question&Answers more detail:os...
asked
Oct 24, 2021
in
Technique[技术]
by
深蓝
(
71.8m
points)
scala
0
votes
1.9k
views
1
answer
scala - Cross-compiling aggregate projects with different crossScalaVersions for subprojects
We have a project with several subprojects which can compile under both Scala 2.10 and 2.11, one subproject ... and still avoid this problem? See Question&Answers more detail:os...
asked
Oct 24, 2021
in
Technique[技术]
by
深蓝
(
71.8m
points)
scala
0
votes
1.9k
views
1
answer
scala - NullPointerException in Spark RDD map when submitted as a spark job
We're trying to submit a spark job (spark 2.0, hadoop 2.7.2) but for some reason we're receiving a ... we resolve it? We're pretty stumped. See Question&Answers more detail:os...
asked
Oct 24, 2021
in
Technique[技术]
by
深蓝
(
71.8m
points)
scala
0
votes
2.1k
views
1
answer
scala - Predict Class Probabilities in Spark RandomForestClassifier
I built random forest models using ml.classification.RandomForestClassifier. I am trying to extract the predict ... or solutions. Thanks! See Question&Answers more detail:os...
asked
Oct 24, 2021
in
Technique[技术]
by
深蓝
(
71.8m
points)
scala
0
votes
2.1k
views
1
answer
scala - How to convert List[Double] to Columns?
I have List[Double], how to convert it to org.apache.spark.sql.Column. I am trying to insert it as ... .withColumn() to existing DataFrame. See Question&Answers more detail:os...
asked
Oct 24, 2021
in
Technique[技术]
by
深蓝
(
71.8m
points)
scala
0
votes
2.0k
views
1
answer
scala - Load Spark data locally Incomplete HDFS URI
I have experienced a problem with SBT loading in a local CSV file. Basically, I've written a Spark program ... under home/projects directory). See Question&Answers more detail:os...
asked
Oct 24, 2021
in
Technique[技术]
by
深蓝
(
71.8m
points)
scala
0
votes
2.2k
views
1
answer
scala - Gatling - execute scenarios sequentialy
When I run code like: setUp( scenario1.inject(constantUsersPerSec(1) during (1 second)), scenario2.inject( ... it one by one? See Question&Answers more detail:os...
asked
Oct 24, 2021
in
Technique[技术]
by
深蓝
(
71.8m
points)
scala
0
votes
2.2k
views
1
answer
scala - Play tests with database: "Too many connections"
To have a database available in scalatest with evolutions I use this extension of the default PlaySpec inspired by this SO ... 10 and Slick 3.1. See Question&Answers more detail:os...
asked
Oct 24, 2021
in
Technique[技术]
by
深蓝
(
71.8m
points)
scala
0
votes
2.1k
views
1
answer
scala - Can I overload curried methods?
Is there a way to overload methods in Scala that take multiple parameter lists? E.g. I'd like to do this ... in some cases, for example. See Question&Answers more detail:os...
asked
Oct 24, 2021
in
Technique[技术]
by
深蓝
(
71.8m
points)
scala
0
votes
2.5k
views
1
answer
scala - Read specific column from Parquet without using Spark
I am trying to read Parquet files without using Apache Spark and I am able to do it but I am finding it ... I want to read specific columns. See Question&Answers more detail:os...
asked
Oct 24, 2021
in
Technique[技术]
by
深蓝
(
71.8m
points)
scala
0
votes
2.1k
views
1
answer
scala - Using dynamic Datasource with Tomcat
I'm creating a series of webservices for my application and i have the need to access a different database ... to add a resource everytime? See Question&Answers more detail:os...
asked
Oct 24, 2021
in
Technique[技术]
by
深蓝
(
71.8m
points)
scala
0
votes
2.0k
views
1
answer
scala - What does Dotty offer to replace type projections?
I have been reading about Dotty, since it looks like it is about to become scala 3, and noticed that type ... cache the result in container } See Question&Answers more detail:os...
asked
Oct 24, 2021
in
Technique[技术]
by
深蓝
(
71.8m
points)
scala
0
votes
2.1k
views
1
answer
scala - Unresolved Dependencies when building play 2.0 project
Downloaded play-2.0 from type safe yesterday, following instructions as far as I can, but when I come to build ... on where to look... Thanks See Question&Answers more detail:os...
asked
Oct 24, 2021
in
Technique[技术]
by
深蓝
(
71.8m
points)
scala
Page:
1
2
3
4
5
6
...
42
next »
Ask a question:
Welcome to OStack Knowledge Sharing Community for programmer and developer-Open, Learning and Share
Click Here to Ask a Question
Just Browsing Browsing
[1] Extract usefull data from html with regex & php
[2] python - cv2.drawContours in a loop not working as expected
[3] recursion - Recursive function always returning same value
[4] qt5 QtWidgets.QPushButton 点击打开新的网页的问题
[5] Angular proxy shows request header failed error
[6] 反馈个挺严重的问题
[7] python - Code using lxml and xpath works on single xml file, but fails when this is extended to a collection of similar xml
[8] cell - Led indicator with 3 LED, but lighting separately
[9] golang 应该如何配置不同环境下的变量
[10] 如何调用接口中的默认方法?
2.1m
questions
2.1m
answers
60
comments
57.0k
users
Most popular tags
javascript
python
c#
java
How
android
c++
php
ios
html
sql
r
c
node.js
.net
iphone
asp.net
css
reactjs
jquery
ruby
What
Android
objective
mysql
linux
Is
git
Python
windows
Why
regex
angular
swift
amazon
excel
algorithm
macos
Java
visual
how
bash
Can
multithreading
PHP
Using
scala
angularjs
typescript
apache
spring
performance
postgresql
database
flutter
json
rust
arrays
C#
dart
vba
django
wpf
xml
vue.js
In
go
Get
google
jQuery
xcode
jsf
http
Google
mongodb
string
shell
oop
powershell
SQL
C++
security
assembly
docker
Javascript
Android:
Does
haskell
Convert
azure
debugging
delphi
vb.net
Spring
datetime
pandas
oracle
math
Django
联盟问答网站-Union QA website
Xstack问答社区
生活宝问答社区
OverStack问答社区
Ostack问答社区
在这了问答社区
在哪了问答社区
Xstack问答社区
无极谷问答社区
TouSu问答社区
SQlite问答社区
Qi-U问答社区
MLink问答社区
Jonic问答社区
Jike问答社区
16892问答社区
Vigges问答社区
55276问答社区
OGeek问答社区
深圳家问答社区
深圳家问答社区
深圳家问答社区
Vigges问答社区
Vigges问答社区
在这了问答社区
DevDocs API Documentations
Xstack问答社区
生活宝问答社区
OverStack问答社区
Ostack问答社区
在这了问答社区
在哪了问答社区
Xstack问答社区
无极谷问答社区
TouSu问答社区
SQlite问答社区
Qi-U问答社区
MLink问答社区
Jonic问答社区
Jike问答社区
16892问答社区
Vigges问答社区
55276问答社区
OGeek问答社区
深圳家问答社区
深圳家问答社区
深圳家问答社区
Vigges问答社区
Vigges问答社区
在这了问答社区
在这了问答社区
DevDocs API Documentations
Xstack问答社区
生活宝问答社区
OverStack问答社区
Ostack问答社区
在这了问答社区
在哪了问答社区
Xstack问答社区
无极谷问答社区
TouSu问答社区
SQlite问答社区
Qi-U问答社区
MLink问答社区
Jonic问答社区
Jike问答社区
16892问答社区
Vigges问答社区
55276问答社区
OGeek问答社区
深圳家问答社区
深圳家问答社区
深圳家问答社区
Vigges问答社区
Vigges问答社区
在这了问答社区
DevDocs API Documentations
广告位招租
...