Document API

[altavir]

There is currently no documentation on interfaces like DataColumn. It makes it hard to add custom implementations for them. For example, it is not clear what ndistinct means.

[altavir]

0.8-rc still has a lot of problems with documentation. For example it is not clear how generic is used here:

dataframe/src/main/kotlin/org/jetbrains/kotlinx/dataframe/DataFrame.kt

Line 22 in db20e69

public interface DataFrame<out T> : Aggregatable<T>, ColumnsContainer<T> {

[nikitinas]

@altavir I've added KDocs for major interfaces, please, check if it's clearer now.

[altavir]

A little bit. But not fully. For example, it is not clear what variance of T is allowed in the schema. Should it be variant T or all descendants of T (for example if T is Number).

The same goes for methods. Some methods are self-explanatory, but some are not. Several examples (just in this class, not going anywhere else):

• dataframe/src/main/kotlin/org/jetbrains/kotlinx/dataframe/DataFrame.kt

  Line 47 in 50dadec

  public fun <R> aggregate(body: AggregateGroupedBody<T, R>): DataRow<T>

  
  What does it do?

• dataframe/src/main/kotlin/org/jetbrains/kotlinx/dataframe/DataFrame.kt

  Line 43 in 50dadec

  public operator fun iterator(): Iterator<DataRow<T>> = rows().iterator()

  
  what is the iteration order?

[nikitinas]

Thank you for quick reply. I'm currently writing KDocs and comments for the library. Probably I'll not be able cover the whole codebase, so your requests for clarification of particular parts of code are appreciated.