init research
This commit is contained in:
+37
@@ -0,0 +1,37 @@
|
||||
[//]: # (title: toList)
|
||||
|
||||
<!---IMPORT org.jetbrains.kotlinx.dataframe.samples.api.Collections-->
|
||||
|
||||
Converts [`DataFrame`](DataFrame.md) into a [`List`](https://kotlinlang.org/api/latest/jvm/stdlib/kotlin.collections/-list/)
|
||||
of data class instances by current [`DataFrame`](DataFrame.md) type argument.
|
||||
|
||||
```
|
||||
toList()
|
||||
```
|
||||
|
||||
**More info**: [](collectionsInterop.md)
|
||||
|
||||
Type of data class is defined by current type argument of [`DataFrame`](DataFrame.md). If this type argument is not data class, exception will be thrown.
|
||||
|
||||
Data class properties are matched with [`DataFrame`](DataFrame.md) columns by name. If property type differs from column type [type conversion](convert.md) will be performed. If no automatic type conversion was found, exception will be thrown.
|
||||
|
||||
To export [`DataFrame`](DataFrame.md) into specific type of data class, use `toListOf`:
|
||||
|
||||
## toListOf
|
||||
|
||||
Converts [`DataFrame`](DataFrame.md) into a [`List`](https://kotlinlang.org/api/latest/jvm/stdlib/kotlin.collections/-list/) of instances of given data class.
|
||||
|
||||
<!---FUN listInterop5-->
|
||||
|
||||
```kotlin
|
||||
val df = dataFrameOf("name", "lastName", "age")("John", "Doe", 21)
|
||||
.group("name", "lastName").into("fullName")
|
||||
|
||||
data class FullName(val name: String, val lastName: String)
|
||||
|
||||
data class Person(val fullName: FullName, val age: Int)
|
||||
|
||||
val persons = df.toListOf<Person>() // [Person(fullName = FullName(name = "John", lastName = "Doe"), age = 21)]
|
||||
```
|
||||
|
||||
<!---END-->
|
||||
Reference in New Issue
Block a user