How to flatten a List of Lists in Scala with flatten
Scala problem: You have a list of lists (or more generally, a sequence of sequences) and want to create one list (sequence) from them.(The following solution comes from the Scala Cookbook, which I...
View ArticleHow to generate random numbers, characters, and sequences in Scala
Scala FAQ: How do I generate random numbers (or characters) in Scala, such as when testing an application, performing a simulation, and many other situations?SolutionCreate random numbers with the...
View ArticleHow to choose a collection class in Scala
This is an excerpt from the Scala Cookbook (partially re-worded for the internet). This is Recipe 10.2.Scala FAQ: How do I choose a Scala collection class to solve a particular problem?SolutionTo being...
View ArticleMake the Vector class your default immutable sequence (Scala best practice)
This is an excerpt from the Scala Cookbook (partially re-worded for the internet). This is Recipe 10.7, “Make the Vector Class Your ‘Go To’ Immutable Sequence.”ProblemYou want a fast, general-purpose,...
View ArticleMake the ArrayBuffer class your default mutable indexed sequence (Scala best...
This is an excerpt from the Scala Cookbook (partially re-worded for the internet). This is Recipe 10.8, “Make the Scala ArrayBuffer Class Your ‘Go To’ Mutable Indexed Sequence”ProblemYou want to use a...
View ArticleScala: How to use zipWithIndex or zip to create loop counters
This is an excerpt from the Scala Cookbook (partially modified for the internet). This is Recipe 10.11, “How to Use zipWithIndex or zip to Create Loop Counters”ProblemYou want to loop over a sequential...
View ArticleHow to extract a sequence of elements from a Scala Collection
This is an excerpt from the Scala Cookbook (partially modified for the internet). This is Recipe 10.18, “How to Extract a Sequence of Elements from a Scala Collection”ProblemYou want to extract a...
View ArticleHow to extract unique elements from a Scala sequence
This is an excerpt from the Scala Cookbook (partially modified for the internet). This is Recipe 10.21, “How to Extract Unique Elements from a Scala Sequence”ProblemYou have a collection that contains...
View ArticleHow to merge Scala sequential collections (List, Vector, ArrayBuffer, Array,...
This is an excerpt from the Scala Cookbook (partially modified for the internet). This is Recipe 10.22, “How to Merge Scala Sequential Collections”ProblemYou want to join two sequences into one...
View ArticleHow to populate Scala collections with a Range
This is an excerpt from the Scala Cookbook (partially modified for the internet). This is Recipe 10.25, “How to Populate a Scala Collection with a Range”ProblemYou want to populate a List, Array,...
View ArticleHow to merge (concatenate) Lists in Scala
This is an excerpt from the Scala Cookbook (partially modified for the internet). This is Recipe 11.5, “How to Merge (Concatenate) Lists in Scala”ProblemYou want to merge/concatenate the contents of...
View ArticleScala: How to loop over a collection with for and foreach (plus for loop...
This is an excerpt from the Scala Cookbook (partially modified for the internet). This is Recipe 3.1, “How to loop over a collection with for and foreach (and how a for loop is translated)”ProblemYou...
View ArticleHow to use Scala for loops with multiple counters
This is an excerpt from the Scala Cookbook (partially modified for the internet). This is Recipe 3.2, “How to use Scala for loops with multiple counters.”ProblemYou want to create a loop with multiple...
View ArticleHow to use a Scala 'for' loop with embedded 'if' statements (guards)
This is an excerpt from the Scala Cookbook (partially modified for the internet). This is Recipe 3.3, “How to use a 'for' loop with embedded 'if' statements (guards).”ProblemYou want to add one or more...
View ArticleHow to drop the first matching element in a Scala sequence
Summary: This blog post shows one way to drop/filter the first matching element from a Scala sequence (Seq, List, Vector, Array, etc.). I don’t claim that the algorithm is efficient, but it does...
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