init research

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+# associate
+
+<web-summary>
+Discover `associate` operation for Kotlin DataFrame.
+</web-summary>
+
+<card-summary>
+Discover `associate` operation for Kotlin DataFrame.
+</card-summary>
+
+<link-summary>
+Discover `associate` operation for Kotlin DataFrame.
+</link-summary>
+
+<!---IMPORT org.jetbrains.kotlinx.dataframe.samples.api.collectionsInterop.AssociateSamples-->
+
+The `associate` function builds a `Map` from key–value `Pair`s produced by applying a transformation to each row
+of this [`DataFrame`](DataFrame.md)
+using a [row expression](DataRow.md#row-expressions).
+
+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`](https://kotlinlang.org/api/core/kotlin-stdlib/kotlin.sequences/associate.html) function.
+
+```kotlin
+df.associate { pairSelector }
+
+pairSelector: (DataRow) -> Pair
+```
+
+### Related functions
+- [`toMap`](toMap.md) — converts a [`DataFrame`](DataFrame.md) into a `Map` by using column names as keys and their values as map values.
+- [`associateBy`](associateBy.md) — creates a map with rows as values.
+
+### Example
+
+<!---FUN notebook_test_associate_1-->
+
+```kotlin
+df
+```
+
+<!---END-->
+
+<inline-frame src="./resources/notebook_test_associate_1.html" width="100%" height="500px"></inline-frame>
+
+Create a map from name to age using a pair selector:
+
+<!---FUN notebook_test_associate_2-->
+
+```kotlin
+df.associate { "${name.firstName} ${name.lastName}" to age }
+```
+
+<!---END-->
+
+Output:
+
+```text
+{
+  Alice Cooper: 15,
+  Bob Dylan: 45,
+  Charlie Daniels: 20,
+  Charlie Chaplin: 40,
+  Bob Marley: 30,
+  Alice Wolf: 20,
+  Charlie Byrd: 30
+}
+```