Scala allows you to do this in a much cleaner way than the standard `String` API by leveraging the collections API (for which there is an implicit conversion from a `java.lang.String` into an `IndexedSeq[Char]`):

    str takeRight 2

The fantastic thing about the API of course, is that it preserves the type representation of the original &quot;collection&quot; (i.e. `String` in this case)!

you can use 

    .takeRight(2)


----------


    var keyword=&quot;helloStackoverFlow&quot;

    println(keyword.takeRight(2)) // ow

You can take (string length -1) that reveal last index of your string, (string length -2) will be next character from end:

`str(str.length-1)+str(str.length-1)`

Say I have an list of objects with two fields `field1` and `field2`, both of String type.

How do I get a list of all `field1` values without having to iterate over the list, if it is at all possible?

How to get a list of specific fields values from objects stored in a list?

I know this is achievable with boost as per:

https://stackoverflow.com/questions/5195990/using-boostaccumulators-how-can-i-reset-a-rolling-window-size-does-it-keep-e

But I really would like to avoid using boost. I have googled and not found any suitable or readable examples.

Basically I want to track the moving average of an ongoing stream of a stream of floating point numbers using the most recent 1000 numbers as a data sample.

What is the easiest way to achieve this?


----------


I experimented with using a circular array, exponential moving average and a more simple moving average and found that the results from the circular array suited my needs best.


Calculate rolling / moving average in C++

How would I return the last two characters of a string?

Scala - Get last two characters from string

<p>How would I return the last two characters of a string?</p>


Here is the current code in my application:

    String[] ids = str.split(&quot;/&quot;);

When profiling the application, a non-negligeable time is spent string splitting. Also, the `split` method takes a regular expression, which is superfluous here.

What alternative can I use in order to optimize the string splitting? Is `StringUtils.split` faster?

(I would&#39;ve tried and tested myself but profiling my application takes a lot of time.)

Java split String performances

How can I convert all values in an array to lowercase in PHP?

Something like `array_change_key_case`?

How to convert array values to lowercase in PHP?

How do i simply write out a file including real tabs inside? `tab` means real `tab` which is **not the spaces**. How to write the `tab` or what is the character for real `tab`?

For example here:

    $chunk = &quot;a,b,c&quot;;
    file_put_contents(&quot;chunk.csv&quot;,$chunk);

What character should i use to get `tabs` instead of `Commas (,)` there?&lt;br&gt;
In the output file, there should be real `tabs` between the seperated words.

- Real Tabs means, **a true wide space we get when we press the `&lt;tab&gt;` key** in a text-editor.

PHP to write Tab Characters inside a file?

I wanted code to convert all the characters in strings to uppercase or lowercase in Java.

I found a method that goes something like this:

    public static String changelowertoupper()
    {
             String str = &quot;CyBeRdRaGoN&quot;;
             str=str.toLowerCase(Locale.ENGLISH);
             return str;
    }
 
Now I&#39;ve read that using certain `Locale`s, like Turkish, &quot;returns ***i (without dot)*** instead of ***i (with dot)***.&quot;

Is it safe to use `Locale`s like UK, US, ENGLISH, etc.? Are there any big differences between them when applied to strings?

Which is the most preferred `Locale` for `String`s?

Using Locales with Java&#39;s toLowerCase() and toUpperCase()

I found three ways to cast a variable to `String` in JavaScript.  
I searched for those three options in the jQuery source code, and **they are all in use**.  
I would like to know if there are any differences between them:

    value.toString()
    String(value)
    value + &quot;&quot;
**[DEMO][1]**



They all produce the same output, but does one of them better than the others?  
I would say the `+ &quot;&quot;` has an advantage that it saves some characters, but that&#39;s not that big advantage, anything else? 


  [1]: http://jsfiddle.net/67NaT/

Casting to string in JavaScript

I am diving into Scala and noticed sbt. I have been quite happy with Gradle in java/groovy projects, and I know there&#39;s a scala plugin for Gradle.

What could be good reasons to favour sbt over Gradle in a Scala project?

comparing sbt and Gradle

I have to say I don&#39;t understand Scala enumeration classes. I can copy-paste the example from documentation, but I have no idea what is going on.


    object WeekDay extends Enumeration {
      type WeekDay = Value
      val Mon, Tue, Wed, Thu, Fri, Sat, Sun = Value
    }
    import WeekDay._

 - What means `type WeekDay = Value` and why do I have to write that? 
 - Why is `val Mon = Value`?  What does that even mean?
 - Why do I have to import the `WeekDay`
   object?  And,
 - when I write `val day = WeekDay.Mon`, why is it type `WeekDay.Value`, not type `WeekDay`?

Understanding scala enumerations

Is there a function that can truncate or round a Double?  At one point in my code I would like a number like: `1.23456789` to be rounded to `1.23`

Scala Doubles, and Precision

If I do the following

     println(3/4)
     &gt;0

I would like to get a decimal answer instead of an integer.  Because of the way I am printing in my actual code I would prefer to cast within the println if that is possible.

Scala Divide two integers and get a float result

I would like to filter my data set on two conditions at once. 

Is it possible?  

I want something like this:

    mystuff = mystuff.filter(_.isX &amp;&amp; _.name == &quot;xyz&quot;)

Content Type	Original Author	Original Content on Stackoverflow
Question	jahilldev	View Question on Stackoverflow
Solution 1 - String	oxbow_lakes	View Answer on Stackoverflow
Solution 2 - String	Govind Singh	View Answer on Stackoverflow
Solution 3 - String	Dinar Gataullin	View Answer on Stackoverflow

Scala - Get last two characters from string

String Problem Overview

String Solutions

Solution 1 - String

Solution 2 - String

Solution 3 - String

Calculate rolling / moving average in C++

How to get a list of specific fields values from objects stored in a list?

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