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dataframe/docs/StardustDocs/topics/ungroup.md

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+[//]: # (title: ungroup)
+
+<!---IMPORT org.jetbrains.kotlinx.dataframe.samples.api.Modify-->
+
+Replaces [`ColumnGroup`](DataColumn.md#columngroup) with its nested columns. 
+
+```text
+ungroup { columns }
+```
+
+**Reverse operation:** [`group`](group.md)
+
+See [column selectors](ColumnSelectors.md) for how to select the columns for this operation.
+
+<!---FUN ungroup-->
+
+```kotlin
+// name.firstName -> firstName
+// name.lastName -> lastName
+df.ungroup { name }
+```
+
+<inline-frame src="resources/org.jetbrains.kotlinx.dataframe.samples.api.Modify.ungroup.html" width="100%"/>
+<!---END-->