How do you concatenate lists in Scala?

How do you concatenate lists in Scala?

In order to concatenate two lists we need to utilize concat() method in Scala. In above syntax, l1 is list1 and l2 is list2. Below is the example to concat two lists in scala. Here, the identical elements are not removed.

What is string * in Scala?

In Scala, as in Java, a string is an immutable object, that is, an object that cannot be modified. On the other hand, objects that can be modified, like arrays, are called mutable objects. Strings are very useful objects, in the rest of this section, we present important methods of java. lang. String class.

How do I concatenate strings in spark?

Since Spark 1.5.0 you can use concat function with DataFrame API:

1. In Python : from pyspark.sql.functions import concat, col, lit df.select(concat(col(“k”), lit(” “), col(“v”)))
2. In Scala : import org.apache.spark.sql.functions.{concat, lit} df.select(concat($”k”, lit(” “), $”v”))

What is string interpolation in scala?

String Interpolation refers to substitution of defined variables or expressions in a given String with respected values. String Interpolation provides an easy way to process String literals. To apply this feature of Scala, we must follow few rules: String must be defined with starting character as s / f /raw.

What is mkString in scala?

The mkString() method is utilized to display all the elements of the list in a string along with a separator. Method Definition: def mkString(sep: String): String. Return Type: It returns all the elements of the list in a string along with a separator.

What is Varargs in Scala?

Most of the programming languages provide us variable length argument mobility to a function, Scala is not a exception. it allows us to indicate that the last argument of the function is a variable length argument. it may be repeated multiple times.

How do I merge two columns in Scala?

Using concat() Function to Concatenate DataFrame Columns This statement creates “FullName” column by concatenating columns fname , mname , lname separating by delimiter comma. To add a delimiter, we have used lit() function. This yields output with just a concatenated column.

How to find string in list using Scala?

var fs = printf(“The value of the float variable is ” + “%f, while the value of the integer ” + “variable is %d, and the string” + “is %s”, floatVar, intVar, stringVar); println(fs) } } Save the above program in Demo.scala. The following commands are used to compile and execute this program.

How can I cast integer to string in Scala?

scala> val i = “1”.toInt i: Int = 1 As you can see, I just cast the string “1” to an Int object using the toInt method, which is available to any String. However, beware that this can fail with a NumberFormatException just like it does in Java, like this: scala> val i = “foo”.toInt java.lang.NumberFormatException: For input string: “foo” so you

How to find the length of a string in Scala?

char charAt (int index) → Returns the character at the specified index.

String replace (char c1,char c2) → Returns a new string resulting by replacing all occurrences of c1 in this string with c2.

String[]split (String reg1) → Splits this string around matches of the given regular expression.

How to generate JSON using Scala?

data(“first_name”)//ujson.Value = Str (“Phil”)

data(“first_name”).str//String = “Phil”

data(“first_name”).value//Any = “Phil”