associate
The associate function builds a Map from key–value Pairs produced by applying a transformation to each row of this DataFrame using a row expression.
If multiple rows produce the same key, only the last value for that key is kept. This matches the behavior of Kotlin’s standard kotlin.collections.associate function.
df.associate { pairSelector }
pairSelector: (DataRow) -> Pair
Related functions
toMap— converts aDataFrameinto aMapby using column names as keys and their values as map values.associateBy— creates a map with rows as values.
Example
df
Create a map from name to age using a pair selector:
df.associate { "${name.firstName} ${name.lastName}" to age }
Output:
{
Alice Cooper: 15,
Bob Dylan: 45,
Charlie Daniels: 20,
Charlie Chaplin: 40,
Bob Marley: 30,
Alice Wolf: 20,
Charlie Byrd: 30
}
18 September 2025