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+[//]: # (title: reorder)
+
+<!---IMPORT org.jetbrains.kotlinx.dataframe.samples.api.Modify-->
+
+Returns [`DataFrame`](DataFrame.md) with a new order of selected columns.
+
+```text
+reorder { columns }
+  [.cast<ColumnType>() ]
+   .by { columnExpression } | .byDesc { columnExpression } | .byName(desc = false)
+    
+columnExpression: DataColumn.(DataColumn) -> Value
+```
+
+**Related operations**: [](moveRename.md)
+
+See [column selectors](ColumnSelectors.md) for how to select the columns for this operation.
+
+<!---FUN reorder-->
+<tabs>
+<tab title="Properties">
+
+```kotlin
+df.reorder { age..isHappy }.byName()
+```
+
+</tab>
+<tab title="Strings">
+
+```kotlin
+    df.reorder { "age".."isHappy" }.byName()
+}
+```
+
+</tab></tabs>
+<inline-frame src="resources/org.jetbrains.kotlinx.dataframe.samples.api.Modify.reorder.html" width="100%"/>
+<!---END-->
+
+When a subset of columns is selected they will be reordered among their original positions. Positions of other columns will not change. 
+
+If selected columns belong to different column groups they will be reordered within their groups, so column grouping will be preserved.
+
+<!---FUN reorderSome-->
+
+```kotlin
+val df = dataFrameOf("c", "d", "a", "b")(
+    3, 4, 1, 2,
+    1, 1, 1, 1,
+)
+df.reorder("d", "b").cast<Int>().by { sum() } // [c, b, a, d]
+```
+
+<!---END-->
+
+When exactly one [`ColumnGroup`](DataColumn.md#columngroup) is selected, reordering is applied to its nested columns.
+
+<!---FUN reorderInGroup-->
+
+```kotlin
+df.reorder { name }.byName(desc = true) // [name.lastName, name.firstName]
+```
+
+<inline-frame src="resources/org.jetbrains.kotlinx.dataframe.samples.api.Modify.reorderInGroup.html" width="100%"/>
+<!---END-->
+
+## reorderColumnsBy
+
+Reorders all columns
+
+```text
+reorderColumnsBy(atAnyDepth = true, desc = false) { columnExpression }
+```
+
+**Parameters:**
+* `atAnyDepth` — reorder columns inside [`ColumnGroups`](DataColumn.md#columngroup) and [`FrameColumn`](DataColumn.md#framecolumn) recursively
+* `desc` — apply descending order
+
+## reorderColumnsByName
+
+```text
+reorderColumnsByName(atAnyDepth = true, desc = false)
+```
+
+**Parameters:**
+* `atAnyDepth` — reorder columns inside [`ColumnGroups`](DataColumn.md#columngroup) and [`FrameColumn`](DataColumn.md#framecolumn) recursively
+* `desc` — apply descending order