From 8011d33263b4e9968eeffd6056cb147569c37753 Mon Sep 17 00:00:00 2001
From: "andrei.kislitsyn" <kisandy@yandex.ru>
Date: Fri, 22 Aug 2025 15:02:47 +0400
Subject: [PATCH 1/8] small functions tests and kdocs

---
 .../jetbrains/kotlinx/dataframe/api/any.kt    | 28 ++++++++
 .../kotlinx/dataframe/api/asIterable.kt       |  5 ++
 .../kotlinx/dataframe/api/asSequence.kt       |  8 +++
 .../kotlinx/dataframe/api/associate.kt        | 49 +++++++++++++
 .../kotlinx/dataframe/api/between.kt          | 12 ++++
 .../documentation/RowFilterDescription.kt     |  8 ++-
 .../kotlinx/dataframe/examples/plugin/Main.kt |  2 +
 .../kotlinx/dataframe/api/FunctionsStdTest.kt | 71 +++++++++++++++++++
 8 files changed, 180 insertions(+), 3 deletions(-)
 create mode 100644 tests/src/test/kotlin/org/jetbrains/kotlinx/dataframe/api/FunctionsStdTest.kt

diff --git a/core/src/main/kotlin/org/jetbrains/kotlinx/dataframe/api/any.kt b/core/src/main/kotlin/org/jetbrains/kotlinx/dataframe/api/any.kt
index 745963dfa1..0c021125f4 100644
--- a/core/src/main/kotlin/org/jetbrains/kotlinx/dataframe/api/any.kt
+++ b/core/src/main/kotlin/org/jetbrains/kotlinx/dataframe/api/any.kt
@@ -2,18 +2,46 @@ package org.jetbrains.kotlinx.dataframe.api
 
 import org.jetbrains.kotlinx.dataframe.DataColumn
 import org.jetbrains.kotlinx.dataframe.DataFrame
+import org.jetbrains.kotlinx.dataframe.DataRow
 import org.jetbrains.kotlinx.dataframe.Predicate
 import org.jetbrains.kotlinx.dataframe.RowFilter
 import org.jetbrains.kotlinx.dataframe.columns.values
 
 // region DataColumn
 
+/**
+ * Returns `true` if at least one element in this [DataColumn] satisfies the given [predicate].
+ *
+ * This is a convenience alias that delegates to [Iterable.any] on the column's [values].
+ *
+ * @param predicate A lambda function that takes a value from the column
+ * and returns `true` if it matches the condition.
+ * @return `true` if at least one element matches the [predicate], `false` otherwise.
+ * @see [DataColumn.all]
+ * @see [DataColumn.filter]
+ * @see [DataColumn.count]
+ */
 public fun <T> DataColumn<T>.any(predicate: Predicate<T>): Boolean = values.any(predicate)
 
 // endregion
 
 // region DataFrame
 
+/**
+ * Returns `true` if at least one row in this [DataFrame] satisfies the given [predicate].
+ *
+ * {@include [org.jetbrains.kotlinx.dataframe.documentation.RowFilterDescription]}
+ *
+ * ### Example
+ * ```kotlin
+ * // Check if there is at least one row where "age" is greater than 18
+ * val hasAdults = df.any { age > 18 }
+ * ```
+ *
+ * @param predicate A [RowFilter] lambda that takes a [DataRow] (as both `this` and `it`)
+ * and returns `true` if the row should be considered a match.
+ * @return `true` if at least one row satisfies the [predicate], `false` otherwise.
+ */
 public inline fun <T> DataFrame<T>.any(predicate: RowFilter<T>): Boolean = rows().any { predicate(it, it) }
 
 // endregion
diff --git a/core/src/main/kotlin/org/jetbrains/kotlinx/dataframe/api/asIterable.kt b/core/src/main/kotlin/org/jetbrains/kotlinx/dataframe/api/asIterable.kt
index 2b5c379f4b..a50bc4f111 100644
--- a/core/src/main/kotlin/org/jetbrains/kotlinx/dataframe/api/asIterable.kt
+++ b/core/src/main/kotlin/org/jetbrains/kotlinx/dataframe/api/asIterable.kt
@@ -4,6 +4,11 @@ import org.jetbrains.kotlinx.dataframe.DataColumn
 
 // region DataColumn
 
+/**
+ * Returns an [Iterable] over the values of this [DataColumn].
+ *
+ * @see [asSequence]
+ */
 public fun <T> DataColumn<T>.asIterable(): Iterable<T> = values()
 
 // endregion
diff --git a/core/src/main/kotlin/org/jetbrains/kotlinx/dataframe/api/asSequence.kt b/core/src/main/kotlin/org/jetbrains/kotlinx/dataframe/api/asSequence.kt
index 73af1ef413..abd7a892c7 100644
--- a/core/src/main/kotlin/org/jetbrains/kotlinx/dataframe/api/asSequence.kt
+++ b/core/src/main/kotlin/org/jetbrains/kotlinx/dataframe/api/asSequence.kt
@@ -6,12 +6,20 @@ import org.jetbrains.kotlinx.dataframe.DataRow
 
 // region DataColumn
 
+/**
+ * Returns a [Sequence] over the values of this [DataColumn].
+ *
+ * @see [asIterable]
+ */
 public fun <T> DataColumn<T>.asSequence(): Sequence<T> = asIterable().asSequence()
 
 // endregion
 
 // region DataFrame
 
+/**
+ * Returns a [Sequence] of [DataRow] over this [DataFrame].
+ */
 public fun <T> DataFrame<T>.asSequence(): Sequence<DataRow<T>> = rows().asSequence()
 
 // endregion
diff --git a/core/src/main/kotlin/org/jetbrains/kotlinx/dataframe/api/associate.kt b/core/src/main/kotlin/org/jetbrains/kotlinx/dataframe/api/associate.kt
index a6dce766ac..0d26dec921 100644
--- a/core/src/main/kotlin/org/jetbrains/kotlinx/dataframe/api/associate.kt
+++ b/core/src/main/kotlin/org/jetbrains/kotlinx/dataframe/api/associate.kt
@@ -3,12 +3,61 @@ package org.jetbrains.kotlinx.dataframe.api
 import org.jetbrains.kotlinx.dataframe.DataFrame
 import org.jetbrains.kotlinx.dataframe.DataRow
 import org.jetbrains.kotlinx.dataframe.RowExpression
+import org.jetbrains.kotlinx.dataframe.RowFilter
+import org.jetbrains.kotlinx.dataframe.documentation.ExtensionPropertiesAPIDocs
 
 // region DataFrame
 
+/**
+ * Builds a [Map] where each key is produced by applying [transform] to a row,
+ * and the value is the corresponding [DataRow].
+ *
+ * The [transform] is a [RowExpression] — a lambda that receives each [DataRow]
+ * both as `this` and `it` and is expected to return a key, allowing you to compute keys directly from row values.
+ * You can also use [extension properties][ExtensionPropertiesAPIDocs] for concise and type-safe access.
+ *
+ * If multiple rows produce the same key, the last row for that key is stored,
+ * consistent with Kotlin's [kotlin.collections.associateBy] behavior.
+ *
+ * See also:
+ * - [toMap] — converts a [DataFrame] into a [Map] by using column names as keys
+ *   and their values as the corresponding map values.
+ *
+ * ### Example
+ * ```kotlin
+ * // Associate each row by the "id" column
+ * val map = df.associateBy { id }
+ * ```
+ *
+ * @param transform A [RowExpression] that returns a key for each row.
+ * @return A [Map] of keys to corresponding rows.
+ */
 public inline fun <T, V> DataFrame<T>.associateBy(transform: RowExpression<T, V>): Map<V, DataRow<T>> =
     rows().associateBy { transform(it, it) }
 
+/**
+ * Builds a [Map] from key-value [Pair]s produced by applying [transform] to each row.
+ *
+ * The [transform] is a [RowExpression] — a lambda that receives each [DataRow]
+ * both as `this` and `it` and is expected to return a pair, allowing you to generate [Pair]s of keys and values from row contents.
+ * You can also use [extension properties][ExtensionPropertiesAPIDocs] for concise and type-safe access.
+ *
+ * If multiple rows produce the same key, the last value for that key is stored,
+ * consistent with Kotlin's [kotlin.collections.associate] behavior.
+ *
+ * See also:
+ * - [toMap] — converts a [DataFrame] into a [Map] by using column names as keys
+ *   and their values as the corresponding map values.
+ *
+ * ### Example
+ * ```kotlin
+ * // Associate rows into a map where key = id, value = name
+ * val map = df.associate { id to name }
+ * ```
+ *
+ * @param transform A [RowExpression] that returns a [Pair] of key and value for each row.
+ * @return A [Map] of keys to values.
+ */
 public inline fun <T, K, V> DataFrame<T>.associate(transform: RowExpression<T, Pair<K, V>>): Map<K, V> =
     rows().associate { transform(it, it) }
 
diff --git a/core/src/main/kotlin/org/jetbrains/kotlinx/dataframe/api/between.kt b/core/src/main/kotlin/org/jetbrains/kotlinx/dataframe/api/between.kt
index 3a37f9e7df..6390a082bb 100644
--- a/core/src/main/kotlin/org/jetbrains/kotlinx/dataframe/api/between.kt
+++ b/core/src/main/kotlin/org/jetbrains/kotlinx/dataframe/api/between.kt
@@ -5,6 +5,18 @@ import org.jetbrains.kotlinx.dataframe.impl.between
 
 // region DataColumn
 
+/**
+ * Returns a [DataColumn] of [Boolean] values indicating whether each element
+ * lies between [left] and [right].
+ *
+ * If [includeBoundaries] is `true` (default), values equal to [left] or [right] are also considered in range.
+ *
+ * @param left The lower boundary of the range.
+ * @param right The upper boundary of the range.
+ * @param includeBoundaries Whether to include [left] and [right] values in the range check. Defaults to `true`.
+ * @return A [DataColumn] of [Boolean] values where each element indicates if the corresponding
+ *         value is within the specified range.
+ */
 public fun <T : Comparable<T>> DataColumn<T>.between(
     left: T,
     right: T,
diff --git a/core/src/main/kotlin/org/jetbrains/kotlinx/dataframe/documentation/RowFilterDescription.kt b/core/src/main/kotlin/org/jetbrains/kotlinx/dataframe/documentation/RowFilterDescription.kt
index dcafe287f2..71bfbe9fb4 100644
--- a/core/src/main/kotlin/org/jetbrains/kotlinx/dataframe/documentation/RowFilterDescription.kt
+++ b/core/src/main/kotlin/org/jetbrains/kotlinx/dataframe/documentation/RowFilterDescription.kt
@@ -4,8 +4,10 @@ import org.jetbrains.kotlinx.dataframe.DataRow
 import org.jetbrains.kotlinx.dataframe.RowFilter
 
 /**
- * The [predicate] is a [RowFilter] — a lambda that receives each [DataRow] both as `this` and `it`,
- * allowing you to define a [Boolean] condition using the row's values,
- * including through [extension properties][ExtensionPropertiesAPIDocs] for convenient access.
+ * The [predicate] is a [RowFilter] — a lambda that receives each [DataRow] as both `this` and `it`
+ * and is expected to return a [Boolean] value.
+ *
+ * It allows you to define conditions using the row's values directly,
+ * including through [extension properties][ExtensionPropertiesAPIDocs] for convenient and type-safe access.
  */
 internal interface RowFilterDescription
diff --git a/examples/kotlin-dataframe-plugin-example/src/main/kotlin/org/jetbrains/kotlinx/dataframe/examples/plugin/Main.kt b/examples/kotlin-dataframe-plugin-example/src/main/kotlin/org/jetbrains/kotlinx/dataframe/examples/plugin/Main.kt
index a1ed3145fa..562d700db3 100644
--- a/examples/kotlin-dataframe-plugin-example/src/main/kotlin/org/jetbrains/kotlinx/dataframe/examples/plugin/Main.kt
+++ b/examples/kotlin-dataframe-plugin-example/src/main/kotlin/org/jetbrains/kotlinx/dataframe/examples/plugin/Main.kt
@@ -6,9 +6,11 @@ import org.jetbrains.kotlinx.dataframe.api.add
 import org.jetbrains.kotlinx.dataframe.api.convert
 import org.jetbrains.kotlinx.dataframe.api.convertTo
 import org.jetbrains.kotlinx.dataframe.api.filter
+import org.jetbrains.kotlinx.dataframe.api.insert
 import org.jetbrains.kotlinx.dataframe.api.into
 import org.jetbrains.kotlinx.dataframe.api.rename
 import org.jetbrains.kotlinx.dataframe.api.renameToCamelCase
+import org.jetbrains.kotlinx.dataframe.api.under
 import org.jetbrains.kotlinx.dataframe.api.with
 import org.jetbrains.kotlinx.dataframe.io.readCsv
 import org.jetbrains.kotlinx.dataframe.io.writeCsv
diff --git a/tests/src/test/kotlin/org/jetbrains/kotlinx/dataframe/api/FunctionsStdTest.kt b/tests/src/test/kotlin/org/jetbrains/kotlinx/dataframe/api/FunctionsStdTest.kt
new file mode 100644
index 0000000000..f1f639ea74
--- /dev/null
+++ b/tests/src/test/kotlin/org/jetbrains/kotlinx/dataframe/api/FunctionsStdTest.kt
@@ -0,0 +1,71 @@
+package org.jetbrains.kotlinx.dataframe.api
+
+import io.kotest.matchers.shouldBe
+import org.jetbrains.kotlinx.dataframe.DataColumn
+import org.jetbrains.kotlinx.dataframe.samples.api.TestBase
+import org.junit.Test
+
+@Suppress("UNCHECKED_CAST")
+class FunctionsStdTest : TestBase() {
+
+    @Test
+    fun `DataColumn any`() {
+        val ageCol = df["age"] as DataColumn<Int>
+        ageCol.any { it > 40 } shouldBe true
+        ageCol.any { it > 90 } shouldBe false
+    }
+
+    @Test
+    fun `DataFrame any`() {
+        df.any { "age"<Int>() > 40 && "isHappy"<Boolean>() } shouldBe true
+        df.any { "city"<String?>() == "Berlin" } shouldBe false
+    }
+
+    @Test
+    fun `DataColumn between`() {
+        val ages = listOf(15, 45, 20, 40, 30, 20, 30)
+        val ageCol = df["age"] as DataColumn<Int>
+        ageCol.between(20, 40).toList() shouldBe listOf(false, false, true, true, true, true, true)
+        ageCol.between(20, 40, includeBoundaries = false).toList() shouldBe listOf(false, false, false, false, true, false, true)
+        ageCol.toList() shouldBe ages
+    }
+
+    @Test
+    fun `DataFrame associateBy`() {
+        val byFirstName = df.associateBy { "name"["firstName"]<String>() }
+        val alice = byFirstName["Alice"]!!
+        val aliceName = alice.getColumnGroup("name")
+        aliceName["lastName"] shouldBe "Wolf"
+        alice["age"] shouldBe 20
+
+        val byCity = df.associateBy { "city"<String?>() }
+        val moscow = byCity["Moscow"]!!
+        moscow.getColumnGroup("name")["lastName"] shouldBe "Byrd"
+    }
+
+    @Test
+    fun `DataFrame associate`() {
+        val map = df.associate { "name"["lastName"]<String>() to "age"<Int>() }
+        map.size shouldBe 7
+        map["Marley"] shouldBe 30
+        map["Cooper"] shouldBe 15
+    }
+
+    @Test
+    fun `DataColumn asIterable`() {
+        val ageCol = df["age"] as DataColumn<Int>
+        ageCol.asIterable().toList() shouldBe listOf(15, 45, 20, 40, 30, 20, 30)
+    }
+
+    @Test
+    fun `DataColumn asSequence`() {
+        val ageCol = df["age"] as DataColumn<Int>
+        ageCol.asSequence().take(2).toList() shouldBe listOf(15, 45)
+    }
+
+    @Test
+    fun `DataFrame asSequence`() {
+        val happyCount = df.asSequence().count { it["isHappy"] as Boolean }
+        happyCount shouldBe 5
+    }
+}

From c7aab2f94007d657a5776e19770e4b574ffed19d Mon Sep 17 00:00:00 2001
From: "andrei.kislitsyn" <kisandy@yandex.ru>
Date: Fri, 22 Aug 2025 15:07:41 +0400
Subject: [PATCH 2/8] ktlint format

---
 .../kotlin/org/jetbrains/kotlinx/dataframe/api/associate.kt    | 1 -
 .../org/jetbrains/kotlinx/dataframe/api/FunctionsStdTest.kt    | 3 ++-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/core/src/main/kotlin/org/jetbrains/kotlinx/dataframe/api/associate.kt b/core/src/main/kotlin/org/jetbrains/kotlinx/dataframe/api/associate.kt
index 0d26dec921..1a3264187b 100644
--- a/core/src/main/kotlin/org/jetbrains/kotlinx/dataframe/api/associate.kt
+++ b/core/src/main/kotlin/org/jetbrains/kotlinx/dataframe/api/associate.kt
@@ -3,7 +3,6 @@ package org.jetbrains.kotlinx.dataframe.api
 import org.jetbrains.kotlinx.dataframe.DataFrame
 import org.jetbrains.kotlinx.dataframe.DataRow
 import org.jetbrains.kotlinx.dataframe.RowExpression
-import org.jetbrains.kotlinx.dataframe.RowFilter
 import org.jetbrains.kotlinx.dataframe.documentation.ExtensionPropertiesAPIDocs
 
 // region DataFrame
diff --git a/tests/src/test/kotlin/org/jetbrains/kotlinx/dataframe/api/FunctionsStdTest.kt b/tests/src/test/kotlin/org/jetbrains/kotlinx/dataframe/api/FunctionsStdTest.kt
index f1f639ea74..3340082c4b 100644
--- a/tests/src/test/kotlin/org/jetbrains/kotlinx/dataframe/api/FunctionsStdTest.kt
+++ b/tests/src/test/kotlin/org/jetbrains/kotlinx/dataframe/api/FunctionsStdTest.kt
@@ -26,7 +26,8 @@ class FunctionsStdTest : TestBase() {
         val ages = listOf(15, 45, 20, 40, 30, 20, 30)
         val ageCol = df["age"] as DataColumn<Int>
         ageCol.between(20, 40).toList() shouldBe listOf(false, false, true, true, true, true, true)
-        ageCol.between(20, 40, includeBoundaries = false).toList() shouldBe listOf(false, false, false, false, true, false, true)
+        ageCol.between(20, 40, includeBoundaries = false).toList() shouldBe
+            listOf(false, false, false, false, true, false, true)
         ageCol.toList() shouldBe ages
     }
 

From 0e2cacc9b92821834318ab3d5587b17546811b1e Mon Sep 17 00:00:00 2001
From: "andrei.kislitsyn" <kisandy@yandex.ru>
Date: Sat, 23 Aug 2025 21:55:28 +0400
Subject: [PATCH 3/8] util functions fixes

---
 .../kotlinx/dataframe/api/chunked.kt          | 54 ++++++++++++++++---
 .../jetbrains/kotlinx/dataframe/api/length.kt |  3 ++
 .../kotlinx/dataframe/api/lowercase.kt        |  3 ++
 .../kotlinx/dataframe/api/shuffle.kt          | 22 ++++++++
 .../kotlinx/dataframe/api/uppercase.kt        |  3 ++
 .../dataframe/util/deprecationMessages.kt     |  6 +++
 .../dataframe/api/UtilFunctionsTest.kt        | 46 +++++++++++++++-
 .../kotlinx/dataframe/samples/api/Analyze.kt  |  6 +--
 .../kotlinx/dataframe/samples/api/Modify.kt   | 22 ++++----
 .../testSets/person/DataFrameTests.kt         |  7 +--
 10 files changed, 147 insertions(+), 25 deletions(-)
 rename tests/src/test/kotlin/org/jetbrains/kotlinx/dataframe/api/FunctionsStdTest.kt => core/src/test/kotlin/org/jetbrains/kotlinx/dataframe/api/UtilFunctionsTest.kt (60%)

diff --git a/core/src/main/kotlin/org/jetbrains/kotlinx/dataframe/api/chunked.kt b/core/src/main/kotlin/org/jetbrains/kotlinx/dataframe/api/chunked.kt
index 9aa6ae504f..116e3bafb7 100644
--- a/core/src/main/kotlin/org/jetbrains/kotlinx/dataframe/api/chunked.kt
+++ b/core/src/main/kotlin/org/jetbrains/kotlinx/dataframe/api/chunked.kt
@@ -12,23 +12,65 @@ import org.jetbrains.kotlinx.dataframe.nrow
 import org.jetbrains.kotlinx.dataframe.type
 
 /**
- * Creates a [FrameColumn] from [this] by splitting the dataframe into
- * smaller ones, with their number of rows at most [size].
+ * Splits this [DataFrame] into consecutive chunks of up to [size] rows
+ * and returns them as a [FrameColumn].
+ *
+ * Each element of the resulting [FrameColumn] is a sub-[DataFrame] containing
+ * at most [size] rows. Chunks are formed in order, without overlap.
+ *
+ * @param [size] Maximum number of rows in each chunk. Must be positive.
+ * @param [name] Name of the resulting [FrameColumn]. Defaults to `"groups"`.
+ * @return A [FrameColumn] where each value is a sub-[DataFrame] chunk.
  */
 public fun <T> DataFrame<T>.chunked(size: Int, name: String = "groups"): FrameColumn<T> =
-    chunked(
-        startIndices = 0 until nrow step size,
-        name = name,
-    )
+    chunked(startIndices = 0 until nrow step size, name = name)
 
+/**
+ * Splits this [DataFrame] into chunks starting at the given [startIndices].
+ *
+ * The chunk starting at index `i` ends right before the next start index
+ * or the end of the [DataFrame].
+ * Use this overload when you need custom chunk boundaries.
+ *
+ * @param [startIndices] Zero-based row indices where each new chunk starts.
+ * @param [name] Name of the resulting [FrameColumn]. Defaults to `"groups"`.
+ * @return A [FrameColumn] where each value is a sub-[DataFrame] chunk.
+ */
 public fun <T> DataFrame<T>.chunked(startIndices: Iterable<Int>, name: String = "groups"): FrameColumn<T> =
     chunkedImpl(startIndices, name)
 
+/**
+ * Groups consecutive values of this [DataColumn] into lists of at most [size] elements.
+ *
+ * This works like [kotlin.collections.chunked], but returns a [ValueColumn] instead of a [List].
+ *
+ * @param [size] Maximum number of elements in each chunk. Must be positive.
+ * @return A [ValueColumn] whose elements are lists representing chunks of the original values.
+ */
 public fun <T> DataColumn<T>.chunked(size: Int): ValueColumn<List<T>> {
     val values = toList().chunked(size)
     return DataColumn.createValueColumn(name(), values, getListType(type))
 }
 
+/**
+ * Splits this [ColumnGroup] into a [FrameColumn] of sub-dataframes
+ * with up to [size] rows in each chunk.
+ *
+ * The resulting [FrameColumn] inherits the name of this group.
+ *
+ * @param [size] Maximum number of rows in each sub-dataframe. Must be positive.
+ * @return A [FrameColumn] where each value is a sub-[DataFrame] chunk.
+ */
 public fun <T> ColumnGroup<T>.chunked(size: Int): FrameColumn<T> = chunked(size, name())
 
+/**
+ * Splits a [DataColumn] of [DataRow] into a [FrameColumn] of sub-dataframes
+ * with up to [size] rows in each chunk.
+ *
+ * This is a convenience overload that treats a [DataColumn] of rows
+ * as if it were a [ColumnGroup] (see [ColumnGroup.chunked]).
+ *
+ * @param [size] Maximum number of rows in each sub-dataframe. Must be positive.
+ * @return A [FrameColumn] where each value is a sub-[DataFrame] chunk.
+ */
 public fun <T> DataColumn<DataRow<T>>.chunked(size: Int): FrameColumn<T> = asColumnGroup().chunked(size)
diff --git a/core/src/main/kotlin/org/jetbrains/kotlinx/dataframe/api/length.kt b/core/src/main/kotlin/org/jetbrains/kotlinx/dataframe/api/length.kt
index 3c9eb65afd..57b1a3cbcb 100644
--- a/core/src/main/kotlin/org/jetbrains/kotlinx/dataframe/api/length.kt
+++ b/core/src/main/kotlin/org/jetbrains/kotlinx/dataframe/api/length.kt
@@ -2,9 +2,12 @@ package org.jetbrains.kotlinx.dataframe.api
 
 import org.jetbrains.kotlinx.dataframe.DataColumn
 import org.jetbrains.kotlinx.dataframe.StringCol
+import org.jetbrains.kotlinx.dataframe.util.LENGTH_REPLACE
+import org.jetbrains.kotlinx.dataframe.util.MESSAGE_SHORTCUT
 
 // region StringCol
 
+@Deprecated(MESSAGE_SHORTCUT, ReplaceWith(LENGTH_REPLACE), DeprecationLevel.WARNING)
 public fun StringCol.length(): DataColumn<Int> = map { it?.length ?: 0 }
 
 // endregion
diff --git a/core/src/main/kotlin/org/jetbrains/kotlinx/dataframe/api/lowercase.kt b/core/src/main/kotlin/org/jetbrains/kotlinx/dataframe/api/lowercase.kt
index 1f10f59911..d6df0da0e5 100644
--- a/core/src/main/kotlin/org/jetbrains/kotlinx/dataframe/api/lowercase.kt
+++ b/core/src/main/kotlin/org/jetbrains/kotlinx/dataframe/api/lowercase.kt
@@ -1,9 +1,12 @@
 package org.jetbrains.kotlinx.dataframe.api
 
 import org.jetbrains.kotlinx.dataframe.StringCol
+import org.jetbrains.kotlinx.dataframe.util.LOWERCASE_REPLACE
+import org.jetbrains.kotlinx.dataframe.util.MESSAGE_SHORTCUT
 
 // region StringCol
 
+@Deprecated(MESSAGE_SHORTCUT, ReplaceWith(LOWERCASE_REPLACE), DeprecationLevel.WARNING)
 public fun StringCol.lowercase(): StringCol = map { it?.lowercase() }
 
 // endregion
diff --git a/core/src/main/kotlin/org/jetbrains/kotlinx/dataframe/api/shuffle.kt b/core/src/main/kotlin/org/jetbrains/kotlinx/dataframe/api/shuffle.kt
index dc4f791871..499017607b 100644
--- a/core/src/main/kotlin/org/jetbrains/kotlinx/dataframe/api/shuffle.kt
+++ b/core/src/main/kotlin/org/jetbrains/kotlinx/dataframe/api/shuffle.kt
@@ -7,16 +7,38 @@ import kotlin.random.Random
 
 // region DataColumn
 
+/**
+ * Returns a new [DataColumn] with the same values in random order using the provided [random] source.
+ *
+ * @param [random] Source of randomness to ensure reproducible shuffles when needed.
+ * @return A new [DataColumn] with values reordered randomly.
+ */
 public fun <T> DataColumn<T>.shuffle(random: Random): DataColumn<T> = get(indices.shuffled(random))
 
+/**
+ * Returns a new [DataColumn] with values in random order using the default randomness.
+ *
+ * @return A new [DataColumn] with values reordered randomly.
+ */
 public fun <T> DataColumn<T>.shuffle(): DataColumn<T> = get(indices.shuffled())
 
 // endregion
 
 // region DataFrame
 
+/**
+ * Returns a new [DataFrame] with rows reordered randomly using the provided [random] source.
+ *
+ * @param [random] Source of randomness to ensure reproducible shuffles when needed.
+ * @return A new [DataFrame] with rows in random order.
+ */
 public fun <T> DataFrame<T>.shuffle(random: Random): DataFrame<T> = getRows(indices.shuffled(random))
 
+/**
+ * Returns a new [DataFrame] with rows in random order using the default randomness.
+ *
+ * @return A new [DataFrame] with rows in random order.
+ */
 public fun <T> DataFrame<T>.shuffle(): DataFrame<T> = getRows(indices.shuffled())
 
 // endregion
diff --git a/core/src/main/kotlin/org/jetbrains/kotlinx/dataframe/api/uppercase.kt b/core/src/main/kotlin/org/jetbrains/kotlinx/dataframe/api/uppercase.kt
index e2595534af..f9c8d93b73 100644
--- a/core/src/main/kotlin/org/jetbrains/kotlinx/dataframe/api/uppercase.kt
+++ b/core/src/main/kotlin/org/jetbrains/kotlinx/dataframe/api/uppercase.kt
@@ -1,9 +1,12 @@
 package org.jetbrains.kotlinx.dataframe.api
 
 import org.jetbrains.kotlinx.dataframe.StringCol
+import org.jetbrains.kotlinx.dataframe.util.MESSAGE_SHORTCUT
+import org.jetbrains.kotlinx.dataframe.util.UPPERCASE_REPLACE
 
 // region StringCol
 
+@Deprecated(MESSAGE_SHORTCUT, ReplaceWith(UPPERCASE_REPLACE), DeprecationLevel.WARNING)
 public fun StringCol.uppercase(): StringCol = map { it?.uppercase() }
 
 // endregion
diff --git a/core/src/main/kotlin/org/jetbrains/kotlinx/dataframe/util/deprecationMessages.kt b/core/src/main/kotlin/org/jetbrains/kotlinx/dataframe/util/deprecationMessages.kt
index 5ba002a1de..e003e59cf1 100644
--- a/core/src/main/kotlin/org/jetbrains/kotlinx/dataframe/util/deprecationMessages.kt
+++ b/core/src/main/kotlin/org/jetbrains/kotlinx/dataframe/util/deprecationMessages.kt
@@ -227,6 +227,12 @@ internal const val COL_TYPE_DEPRECATED_INSTANT =
     "kotlinx.datetime.Instant is deprecated in favor of kotlin.time.Instant. Migrate to kotlin.time.Instant and use Coltype.StdlibInstant at your own pace. $MESSAGE_1_1"
 internal const val COL_TYPE_DEPRECATED_INSTANT_REPLACE = "ColType.StdlibInstant"
 
+internal const val MESSAGE_SHORTCUT = "This shortcut is deprecated. $MESSAGE_1_1"
+
+internal const val LENGTH_REPLACE = "this.map { it?.length ?: 0 }"
+internal const val LOWERCASE_REPLACE = "this.map { it?.lowercase() }"
+internal const val UPPERCASE_REPLACE = "this.map { it?.uppercase() }"
+
 // endregion
 
 // region keep across releases
diff --git a/tests/src/test/kotlin/org/jetbrains/kotlinx/dataframe/api/FunctionsStdTest.kt b/core/src/test/kotlin/org/jetbrains/kotlinx/dataframe/api/UtilFunctionsTest.kt
similarity index 60%
rename from tests/src/test/kotlin/org/jetbrains/kotlinx/dataframe/api/FunctionsStdTest.kt
rename to core/src/test/kotlin/org/jetbrains/kotlinx/dataframe/api/UtilFunctionsTest.kt
index 3340082c4b..7fd29fdcf5 100644
--- a/tests/src/test/kotlin/org/jetbrains/kotlinx/dataframe/api/FunctionsStdTest.kt
+++ b/core/src/test/kotlin/org/jetbrains/kotlinx/dataframe/api/UtilFunctionsTest.kt
@@ -3,10 +3,13 @@ package org.jetbrains.kotlinx.dataframe.api
 import io.kotest.matchers.shouldBe
 import org.jetbrains.kotlinx.dataframe.DataColumn
 import org.jetbrains.kotlinx.dataframe.samples.api.TestBase
+import org.jetbrains.kotlinx.dataframe.size
 import org.junit.Test
+import kotlin.collections.map
+import kotlin.random.Random
 
 @Suppress("UNCHECKED_CAST")
-class FunctionsStdTest : TestBase() {
+class UtilFunctionsTest: TestBase() {
 
     @Test
     fun `DataColumn any`() {
@@ -69,4 +72,45 @@ class FunctionsStdTest : TestBase() {
         val happyCount = df.asSequence().count { it["isHappy"] as Boolean }
         happyCount shouldBe 5
     }
+
+    @Test
+    fun `DataFrame chunked`() {
+        val groups = df.chunked(3)
+        groups.size shouldBe 3
+        groups.name() shouldBe "groups"
+        groups[0].rowsCount() shouldBe 3
+        groups[1].rowsCount() shouldBe 3
+        groups[2].rowsCount() shouldBe 1
+    }
+
+    @Test
+    fun `DataColumn chunked`() {
+        val ageCol = df["age"] as DataColumn<Int>
+        val chunked = ageCol.chunked(4)
+        chunked.size shouldBe 2
+        chunked.name() shouldBe "age"
+        // Check chunk contents
+        chunked[0] shouldBe listOf(15, 45, 20, 40)
+        chunked[1] shouldBe listOf(30, 20, 30)
+    }
+
+    @Test
+    fun `DataFrame shuffle`() {
+        val rnd = Random(123)
+        val shuffledDf = df.shuffle(rnd)
+        // Compute expected order via indices.shuffled with same seed
+        val ages = (df["age"] as DataColumn<Int>).toList()
+        val expectedAges = ages.indices.shuffled(Random(123)).map { ages[it] }
+        shuffledDf.rows().map { it["age"] as Int } shouldBe expectedAges
+    }
+
+    @Test
+    fun `DataColumn shuffle`() {
+        val rnd = Random(123)
+        val ageCol = df["age"] as DataColumn<Int>
+        val shuffled = ageCol.shuffle(rnd)
+        val values = ageCol.toList()
+        val expected = values.indices.shuffled(Random(123)).map { values[it] }
+        shuffled.toList() shouldBe expected
+    }
 }
diff --git a/core/src/test/kotlin/org/jetbrains/kotlinx/dataframe/samples/api/Analyze.kt b/core/src/test/kotlin/org/jetbrains/kotlinx/dataframe/samples/api/Analyze.kt
index a7779c3b92..8726e7d362 100644
--- a/core/src/test/kotlin/org/jetbrains/kotlinx/dataframe/samples/api/Analyze.kt
+++ b/core/src/test/kotlin/org/jetbrains/kotlinx/dataframe/samples/api/Analyze.kt
@@ -23,7 +23,7 @@ import org.jetbrains.kotlinx.dataframe.api.groupBy
 import org.jetbrains.kotlinx.dataframe.api.groupByOther
 import org.jetbrains.kotlinx.dataframe.api.head
 import org.jetbrains.kotlinx.dataframe.api.indices
-import org.jetbrains.kotlinx.dataframe.api.length
+import org.jetbrains.kotlinx.dataframe.api.map
 import org.jetbrains.kotlinx.dataframe.api.matches
 import org.jetbrains.kotlinx.dataframe.api.max
 import org.jetbrains.kotlinx.dataframe.api.maxBy
@@ -644,7 +644,7 @@ class Analyze : TestBase() {
         df.groupBy { city }.sum("total weight") { weight } // sum of weights into column "total weight"
         df.groupBy { city }.count() // number of rows into column "count"
         df.groupBy { city }
-            .max { name.firstName.length() and name.lastName.length() } // maximum length of firstName or lastName into column "max"
+            .max { name.firstName.map { it.length } and name.lastName.map { it.length } } // maximum length of firstName or lastName into column "max"
         df.groupBy { city }
             .medianFor { age and weight } // median age into column "age", median weight into column "weight"
         df.groupBy { city }
@@ -663,7 +663,7 @@ class Analyze : TestBase() {
         df.groupBy("city").sum("weight", name = "total weight") // sum of weights into column "total weight"
         df.groupBy("city").count() // number of rows into column "count"
         df.groupBy("city").max {
-            "name"["firstName"]<String>().length() and "name"["lastName"]<String>().length()
+            "name"["firstName"]<String>().map { it.length } and "name"["lastName"]<String>().map { it.length }
         } // maximum length of firstName or lastName into column "max"
         df.groupBy("city")
             .medianFor("age", "weight") // median age into column "age", median weight into column "weight"
diff --git a/core/src/test/kotlin/org/jetbrains/kotlinx/dataframe/samples/api/Modify.kt b/core/src/test/kotlin/org/jetbrains/kotlinx/dataframe/samples/api/Modify.kt
index 1fb498d172..d23c33fdc1 100644
--- a/core/src/test/kotlin/org/jetbrains/kotlinx/dataframe/samples/api/Modify.kt
+++ b/core/src/test/kotlin/org/jetbrains/kotlinx/dataframe/samples/api/Modify.kt
@@ -10,9 +10,7 @@ import org.jetbrains.kotlinx.dataframe.annotations.DataSchema
 import org.jetbrains.kotlinx.dataframe.api.ParserOptions
 import org.jetbrains.kotlinx.dataframe.api.add
 import org.jetbrains.kotlinx.dataframe.api.after
-import org.jetbrains.kotlinx.dataframe.api.and
 import org.jetbrains.kotlinx.dataframe.api.asColumn
-import org.jetbrains.kotlinx.dataframe.api.to
 import org.jetbrains.kotlinx.dataframe.api.asFrame
 import org.jetbrains.kotlinx.dataframe.api.asGroupBy
 import org.jetbrains.kotlinx.dataframe.api.at
@@ -51,8 +49,6 @@ import org.jetbrains.kotlinx.dataframe.api.intoList
 import org.jetbrains.kotlinx.dataframe.api.intoRows
 import org.jetbrains.kotlinx.dataframe.api.inward
 import org.jetbrains.kotlinx.dataframe.api.keysInto
-import org.jetbrains.kotlinx.dataframe.api.length
-import org.jetbrains.kotlinx.dataframe.api.lowercase
 import org.jetbrains.kotlinx.dataframe.api.map
 import org.jetbrains.kotlinx.dataframe.api.mapKeys
 import org.jetbrains.kotlinx.dataframe.api.mapToColumn
@@ -88,11 +84,12 @@ import org.jetbrains.kotlinx.dataframe.api.sortByDesc
 import org.jetbrains.kotlinx.dataframe.api.sortWith
 import org.jetbrains.kotlinx.dataframe.api.split
 import org.jetbrains.kotlinx.dataframe.api.sum
+import org.jetbrains.kotlinx.dataframe.api.to
 import org.jetbrains.kotlinx.dataframe.api.toColumn
 import org.jetbrains.kotlinx.dataframe.api.toFloat
-import org.jetbrains.kotlinx.dataframe.api.toStart
 import org.jetbrains.kotlinx.dataframe.api.toMap
 import org.jetbrains.kotlinx.dataframe.api.toPath
+import org.jetbrains.kotlinx.dataframe.api.toStart
 import org.jetbrains.kotlinx.dataframe.api.toTop
 import org.jetbrains.kotlinx.dataframe.api.under
 import org.jetbrains.kotlinx.dataframe.api.unfold
@@ -115,7 +112,8 @@ import org.junit.Ignore
 import org.junit.Test
 import java.net.URL
 import java.time.format.DateTimeFormatter
-import java.util.*
+import java.util.Locale
+import java.util.Random
 import java.util.stream.Collectors
 
 @Suppress("ktlint:standard:chain-method-continuation", "ktlint:standard:argument-list-wrapping")
@@ -197,7 +195,7 @@ class Modify : TestBase() {
         // SampleStart
         df.convert { age }.to<Double>()
         df.convert { colsOf<Number>() }.to<String>()
-        df.convert { name.firstName and name.lastName }.asColumn { it.length() }
+        df.convert { name.firstName and name.lastName }.asColumn { col -> col.map { it.length } }
         df.convert { weight }.toFloat()
         // SampleEnd
     }
@@ -287,7 +285,7 @@ class Modify : TestBase() {
     fun replace() {
         // SampleStart
         df.replace { name }.with { name.firstName }
-        df.replace { colsOf<String?>() }.with { it.lowercase() }
+        df.replace { colsOf<String?>() }.with { col -> col.map { it?.lowercase() } }
         df.replace { age }.with { 2021 - age named "year" }
         // SampleEnd
     }
@@ -923,7 +921,7 @@ class Modify : TestBase() {
             "year of birth" from 2021 - age
             age gt 18 into "is adult"
             "details" {
-                name.lastName.length() into "last name length"
+                name.lastName.map { it.length } into "last name length"
                 "full name" from { name.firstName + " " + name.lastName }
             }
         }
@@ -938,7 +936,7 @@ class Modify : TestBase() {
             "year of birth" from 2021 - "age"<Int>()
             "age"<Int>() gt 18 into "is adult"
             "details" {
-                "name"["lastName"]<String>().length() into "last name length"
+                "name"["lastName"]<String>().map { it.length } into "last name length"
                 "full name" from { "name"["firstName"]<String>() + " " + "name"["lastName"]<String>() }
             }
         }
@@ -992,7 +990,7 @@ class Modify : TestBase() {
         df.mapToFrame {
             "year of birth" from 2021 - age
             age gt 18 into "is adult"
-            name.lastName.length() into "last name length"
+            name.lastName.map { it.length } into "last name length"
             "full name" from { name.firstName + " " + name.lastName }
             +city
         }
@@ -1006,7 +1004,7 @@ class Modify : TestBase() {
         df.mapToFrame {
             "year of birth" from 2021 - "age"<Int>()
             "age"<Int>() gt 18 into "is adult"
-            "name"["lastName"]<String>().length() into "last name length"
+            "name"["lastName"]<String>().map { it.length } into "last name length"
             "full name" from { "name"["firstName"]<String>() + " " + "name"["lastName"]<String>() }
             +"city"
         }
diff --git a/core/src/test/kotlin/org/jetbrains/kotlinx/dataframe/testSets/person/DataFrameTests.kt b/core/src/test/kotlin/org/jetbrains/kotlinx/dataframe/testSets/person/DataFrameTests.kt
index 435018c912..7b94c6fcbf 100644
--- a/core/src/test/kotlin/org/jetbrains/kotlinx/dataframe/testSets/person/DataFrameTests.kt
+++ b/core/src/test/kotlin/org/jetbrains/kotlinx/dataframe/testSets/person/DataFrameTests.kt
@@ -88,7 +88,6 @@ import org.jetbrains.kotlinx.dataframe.api.isNumber
 import org.jetbrains.kotlinx.dataframe.api.keysInto
 import org.jetbrains.kotlinx.dataframe.api.last
 import org.jetbrains.kotlinx.dataframe.api.leftJoin
-import org.jetbrains.kotlinx.dataframe.api.lowercase
 import org.jetbrains.kotlinx.dataframe.api.map
 import org.jetbrains.kotlinx.dataframe.api.mapToFrame
 import org.jetbrains.kotlinx.dataframe.api.match
@@ -1124,7 +1123,7 @@ class DataFrameTests : BaseTest() {
     @Test
     fun `pivot matches with conversion`() {
         val filtered = typed.dropNulls { city }
-        val res = filtered.pivot(inward = false) { city.lowercase() }.groupBy { name and age }.matches()
+        val res = filtered.pivot(inward = false) { city.map { it?.lowercase() } }.groupBy { name and age }.matches()
         val cities = filtered.city.toList().map { it!!.lowercase() }
         val gathered =
             res.gather { colsOf<Boolean> { cities.contains(it.name()) } }.where { it }.keysInto("city")
@@ -2061,7 +2060,9 @@ class DataFrameTests : BaseTest() {
         typed
             .groupBy { name.map { it.lowercase() } }.toDataFrame()
             .name.values() shouldBe
-            typed.name.distinct().lowercase().values()
+            run {
+                typed.name.distinct().map { it.lowercase() }.values()
+            }
     }
 
     @Test

From ecc5b0ae3891e709b8c4b13c2fea2af8b58e61c7 Mon Sep 17 00:00:00 2001
From: "andrei.kislitsyn" <kisandy@yandex.ru>
Date: Sat, 23 Aug 2025 21:55:59 +0400
Subject: [PATCH 4/8] ktlint format

---
 .../org/jetbrains/kotlinx/dataframe/api/UtilFunctionsTest.kt    | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/core/src/test/kotlin/org/jetbrains/kotlinx/dataframe/api/UtilFunctionsTest.kt b/core/src/test/kotlin/org/jetbrains/kotlinx/dataframe/api/UtilFunctionsTest.kt
index 7fd29fdcf5..a29c37dffd 100644
--- a/core/src/test/kotlin/org/jetbrains/kotlinx/dataframe/api/UtilFunctionsTest.kt
+++ b/core/src/test/kotlin/org/jetbrains/kotlinx/dataframe/api/UtilFunctionsTest.kt
@@ -9,7 +9,7 @@ import kotlin.collections.map
 import kotlin.random.Random
 
 @Suppress("UNCHECKED_CAST")
-class UtilFunctionsTest: TestBase() {
+class UtilFunctionsTest : TestBase() {
 
     @Test
     fun `DataColumn any`() {

From 5ce2a7d9293085ece52d3f7c5cf0bac7093fd9d0 Mon Sep 17 00:00:00 2001
From: "andrei.kislitsyn" <kisandy@yandex.ru>
Date: Tue, 26 Aug 2025 14:13:00 +0400
Subject: [PATCH 5/8] deprecate ColumnReferenceApi

---
 .../dataframe/api/ColumnReferenceApi.kt       | 11 +++++++++++
 .../jetbrains/kotlinx/dataframe/api/gather.kt |  4 ++--
 .../kotlinx/dataframe/api/reverse.kt          |  2 +-
 .../kotlinx/dataframe/samples/api/Create.kt   |  6 +++---
 .../testSets/person/DataFrameTests.kt         | 19 -------------------
 5 files changed, 17 insertions(+), 25 deletions(-)

diff --git a/core/src/main/kotlin/org/jetbrains/kotlinx/dataframe/api/ColumnReferenceApi.kt b/core/src/main/kotlin/org/jetbrains/kotlinx/dataframe/api/ColumnReferenceApi.kt
index 40c90f36d3..3b79e04a93 100644
--- a/core/src/main/kotlin/org/jetbrains/kotlinx/dataframe/api/ColumnReferenceApi.kt
+++ b/core/src/main/kotlin/org/jetbrains/kotlinx/dataframe/api/ColumnReferenceApi.kt
@@ -4,26 +4,37 @@ import org.jetbrains.kotlinx.dataframe.DataColumn
 import org.jetbrains.kotlinx.dataframe.columns.ColumnReference
 import org.jetbrains.kotlinx.dataframe.columns.ValueColumn
 import org.jetbrains.kotlinx.dataframe.impl.asList
+import org.jetbrains.kotlinx.dataframe.util.DEPRECATED_ACCESS_API
 import kotlin.reflect.typeOf
 
 internal val ColumnReference<*>.name: String get() = name()
 
+@Suppress("DEPRECATION_ERROR")
+@Deprecated(DEPRECATED_ACCESS_API, level = DeprecationLevel.ERROR)
 public inline fun <reified T> ColumnReference<T>.withValues(vararg values: T): ValueColumn<T> =
     withValues(values.asIterable())
 
+@Deprecated(DEPRECATED_ACCESS_API, level = DeprecationLevel.ERROR)
 public inline fun <reified T> ColumnReference<T>.withValues(values: Iterable<T>): ValueColumn<T> =
     DataColumn.createValueColumn(name(), values.asList(), typeOf<T>())
 
+@Deprecated(DEPRECATED_ACCESS_API, level = DeprecationLevel.ERROR)
 public infix fun <C : Comparable<C>> ColumnReference<C>.gt(value: C): ColumnReference<Boolean> = map { it > value }
 
+@Deprecated(DEPRECATED_ACCESS_API, level = DeprecationLevel.ERROR)
 public infix fun <C : Comparable<C>> ColumnReference<C>.lt(value: C): ColumnReference<Boolean> = map { it < value }
 
+@Deprecated(DEPRECATED_ACCESS_API, level = DeprecationLevel.ERROR)
 public infix fun <C> ColumnReference<C>.eq(value: C): ColumnReference<Boolean> = map { it == value }
 
+@Deprecated(DEPRECATED_ACCESS_API, level = DeprecationLevel.ERROR)
 public infix fun <C> ColumnReference<C>.neq(value: C): ColumnReference<Boolean> = map { it != value }
 
+@Deprecated(DEPRECATED_ACCESS_API, level = DeprecationLevel.ERROR)
 public fun ColumnReference<String?>.length(): ColumnReference<Int> = map { it?.length ?: 0 }
 
+@Deprecated(DEPRECATED_ACCESS_API, level = DeprecationLevel.ERROR)
 public fun ColumnReference<String?>.lowercase(): ColumnReference<String?> = map { it?.lowercase() }
 
+@Deprecated(DEPRECATED_ACCESS_API, level = DeprecationLevel.ERROR)
 public fun ColumnReference<String?>.uppercase(): ColumnReference<String?> = map { it?.uppercase() }
diff --git a/core/src/test/kotlin/org/jetbrains/kotlinx/dataframe/api/gather.kt b/core/src/test/kotlin/org/jetbrains/kotlinx/dataframe/api/gather.kt
index d9594d0878..59885d4b92 100644
--- a/core/src/test/kotlin/org/jetbrains/kotlinx/dataframe/api/gather.kt
+++ b/core/src/test/kotlin/org/jetbrains/kotlinx/dataframe/api/gather.kt
@@ -106,8 +106,8 @@ class GatherTests {
                 val dataRows = cols.map { it[0] }
 
                 val newDf = listOf(
-                    name.withValues(List(cols.size) { name[0] }),
-                    mode.withValues(cols.map { it.name() }),
+                    List(cols.size) { name[0] }.toColumn("name"),
+                    cols.map { it.name() }.toColumn("mode"),
                     dataRows.map { it.getValueOrNull<String>("c1") }.toColumn("c1"),
                     dataRows.map { it.getValueOrNull<String>("c2") }.toColumn("c2"),
                     dataRows.map { it.getValueOrNull<String>("c3") }.toColumn("c3"),
diff --git a/core/src/test/kotlin/org/jetbrains/kotlinx/dataframe/api/reverse.kt b/core/src/test/kotlin/org/jetbrains/kotlinx/dataframe/api/reverse.kt
index 39f351db9f..227584b6f8 100644
--- a/core/src/test/kotlin/org/jetbrains/kotlinx/dataframe/api/reverse.kt
+++ b/core/src/test/kotlin/org/jetbrains/kotlinx/dataframe/api/reverse.kt
@@ -14,7 +14,7 @@ class ReverseTests {
     @Test
     fun column() {
         val col by columnOf(1, 2, 3)
-        col.reverse() shouldBe col.withValues(listOf(3, 2, 1))
+        col.reverse() shouldBe listOf(3, 2, 1).toColumn("col")
     }
 
     @Test
diff --git a/core/src/test/kotlin/org/jetbrains/kotlinx/dataframe/samples/api/Create.kt b/core/src/test/kotlin/org/jetbrains/kotlinx/dataframe/samples/api/Create.kt
index 2335cde5b0..9dfa164049 100644
--- a/core/src/test/kotlin/org/jetbrains/kotlinx/dataframe/samples/api/Create.kt
+++ b/core/src/test/kotlin/org/jetbrains/kotlinx/dataframe/samples/api/Create.kt
@@ -25,7 +25,6 @@ import org.jetbrains.kotlinx.dataframe.api.toColumn
 import org.jetbrains.kotlinx.dataframe.api.toColumnOf
 import org.jetbrains.kotlinx.dataframe.api.toDataFrame
 import org.jetbrains.kotlinx.dataframe.api.value
-import org.jetbrains.kotlinx.dataframe.api.withValues
 import org.jetbrains.kotlinx.dataframe.columns.ColumnKind
 import org.jetbrains.kotlinx.dataframe.explainer.TransformDataFrameExpressions
 import org.jetbrains.kotlinx.dataframe.kind
@@ -79,7 +78,8 @@ class Create : TestBase() {
         // SampleEnd
     }
 
-    @Test
+    // Not used anymore
+    /*@Test
     @TransformDataFrameExpressions
     fun columnAccessorToColumn() {
         // SampleStart
@@ -89,7 +89,7 @@ class Create : TestBase() {
         // SampleEnd
 
         ageCol2.size() shouldBe 10
-    }
+    }*/
 
     @Test
     @TransformDataFrameExpressions
diff --git a/core/src/test/kotlin/org/jetbrains/kotlinx/dataframe/testSets/person/DataFrameTests.kt b/core/src/test/kotlin/org/jetbrains/kotlinx/dataframe/testSets/person/DataFrameTests.kt
index 7b94c6fcbf..68eba9ec32 100644
--- a/core/src/test/kotlin/org/jetbrains/kotlinx/dataframe/testSets/person/DataFrameTests.kt
+++ b/core/src/test/kotlin/org/jetbrains/kotlinx/dataframe/testSets/person/DataFrameTests.kt
@@ -158,7 +158,6 @@ import org.jetbrains.kotlinx.dataframe.api.valuesNotNull
 import org.jetbrains.kotlinx.dataframe.api.where
 import org.jetbrains.kotlinx.dataframe.api.with
 import org.jetbrains.kotlinx.dataframe.api.withNull
-import org.jetbrains.kotlinx.dataframe.api.withValues
 import org.jetbrains.kotlinx.dataframe.api.withZero
 import org.jetbrains.kotlinx.dataframe.api.xs
 import org.jetbrains.kotlinx.dataframe.columns.ColumnKind
@@ -247,24 +246,6 @@ class DataFrameTests : BaseTest() {
         val d = dataFrameOf(a, b)
     }
 
-    @Test
-    fun `create column reference`() {
-        val name by column<String>()
-        val col = name.withValues("Alice", "Bob")
-        val df = col.toDataFrame()
-        df.nrow shouldBe 2
-        df.columnNames() shouldBe listOf("name")
-    }
-
-    @Test
-    fun `add values to column reference`() {
-        val name by column<String>()
-        val values = listOf("Alice", "Bob")
-        val col1 = name.withValues(values)
-        val col2 = values.toColumn(name)
-        col1 shouldBe col2
-    }
-
     @Test
     fun `create from map`() {
         val data = mapOf("name" to listOf("Alice", "Bob"), "age" to listOf(15, null))

From 5ec6fd21803ce143803fb578cb0b3639e3014a34 Mon Sep 17 00:00:00 2001
From: "andrei.kislitsyn" <kisandy@yandex.ru>
Date: Tue, 26 Aug 2025 14:37:56 +0400
Subject: [PATCH 6/8] deprecate tail

---
 .../main/kotlin/org/jetbrains/kotlinx/dataframe/api/tail.kt    | 3 +++
 .../jetbrains/kotlinx/dataframe/util/deprecationMessages.kt    | 3 +++
 2 files changed, 6 insertions(+)

diff --git a/core/src/main/kotlin/org/jetbrains/kotlinx/dataframe/api/tail.kt b/core/src/main/kotlin/org/jetbrains/kotlinx/dataframe/api/tail.kt
index 1228924f45..c2b652e977 100644
--- a/core/src/main/kotlin/org/jetbrains/kotlinx/dataframe/api/tail.kt
+++ b/core/src/main/kotlin/org/jetbrains/kotlinx/dataframe/api/tail.kt
@@ -1,9 +1,12 @@
 package org.jetbrains.kotlinx.dataframe.api
 
 import org.jetbrains.kotlinx.dataframe.DataFrame
+import org.jetbrains.kotlinx.dataframe.util.TAIL
+import org.jetbrains.kotlinx.dataframe.util.TAIL_REPLACE
 
 // region DataFrame
 
+@Deprecated(TAIL, ReplaceWith(TAIL_REPLACE), DeprecationLevel.ERROR)
 public fun <T> DataFrame<T>.tail(numRows: Int = 5): DataFrame<T> = takeLast(numRows)
 
 // endregion
diff --git a/core/src/main/kotlin/org/jetbrains/kotlinx/dataframe/util/deprecationMessages.kt b/core/src/main/kotlin/org/jetbrains/kotlinx/dataframe/util/deprecationMessages.kt
index e003e59cf1..7d1ff25477 100644
--- a/core/src/main/kotlin/org/jetbrains/kotlinx/dataframe/util/deprecationMessages.kt
+++ b/core/src/main/kotlin/org/jetbrains/kotlinx/dataframe/util/deprecationMessages.kt
@@ -137,6 +137,9 @@ internal const val COL_TYPE_INSTANT =
     "kotlinx.datetime.Instant is deprecated in favor of kotlin.time.Instant. Either migrate to kotlin.time.Instant and use ColType.StdlibInstant or use ColType.DeprecatedInstant. $MESSAGE_1_0 and migrated to kotlin.time.Instant in 1.1."
 internal const val COL_TYPE_INSTANT_REPLACE = "ColType.DeprecatedInstant"
 
+internal const val TAIL = "This function will be removed in favor of `takeLast()`. $MESSAGE_1_0"
+internal const val TAIL_REPLACE = "this.takeLast(numRows)"
+
 // endregion
 
 // region WARNING in 1.0, ERROR in 1.1

From c11d7704c09aeb320074cfe34192da51eb13209d Mon Sep 17 00:00:00 2001
From: "andrei.kislitsyn" <kisandy@yandex.ru>
Date: Wed, 27 Aug 2025 13:16:59 +0400
Subject: [PATCH 7/8] wine notebook update tail -> takeLast

---
 examples/notebooks/dev/wine/WineNetWIthKotlinDL.ipynb | 6 ++----
 examples/notebooks/wine/WineNetWIthKotlinDL.ipynb     | 6 ++----
 2 files changed, 4 insertions(+), 8 deletions(-)

diff --git a/examples/notebooks/dev/wine/WineNetWIthKotlinDL.ipynb b/examples/notebooks/dev/wine/WineNetWIthKotlinDL.ipynb
index 8bab36888d..7d154e292f 100644
--- a/examples/notebooks/dev/wine/WineNetWIthKotlinDL.ipynb
+++ b/examples/notebooks/dev/wine/WineNetWIthKotlinDL.ipynb
@@ -2294,9 +2294,7 @@
      "start_time": "2025-08-04T19:11:29.971573Z"
     }
    },
-   "source": [
-    "trainHist.epochHistory.toDataFrame().tail()"
-   ],
+   "source": "trainHist.epochHistory.toDataFrame().takeLast()",
    "outputs": [
     {
      "data": {
@@ -3251,7 +3249,7 @@
    },
    "source": [
     "val trainHist = model2.fit(train, batchSize = 500, epochs = 2000)\n",
-    "trainHist.epochHistory.toDataFrame().tail()"
+    "trainHist.epochHistory.toDataFrame().takeLast()"
    ],
    "outputs": [
     {
diff --git a/examples/notebooks/wine/WineNetWIthKotlinDL.ipynb b/examples/notebooks/wine/WineNetWIthKotlinDL.ipynb
index 9b9738c78b..4b809be639 100644
--- a/examples/notebooks/wine/WineNetWIthKotlinDL.ipynb
+++ b/examples/notebooks/wine/WineNetWIthKotlinDL.ipynb
@@ -2291,9 +2291,7 @@
      "start_time": "2025-05-28T10:59:34.101283Z"
     }
    },
-   "source": [
-    "trainHist.epochHistory.toDataFrame().tail()"
-   ],
+   "source": "trainHist.epochHistory.toDataFrame().takeLast()",
    "outputs": [
     {
      "data": {
@@ -3248,7 +3246,7 @@
    },
    "source": [
     "val trainHist = model2.fit(train, batchSize = 500, epochs = 2000)\n",
-    "trainHist.epochHistory.toDataFrame().tail()"
+    "trainHist.epochHistory.toDataFrame().takeLast()"
    ],
    "outputs": [
     {

From 86a46307ac27309b7289ecebb9073161c2040a69 Mon Sep 17 00:00:00 2001
From: "andrei.kislitsyn" <kisandy@yandex.ru>
Date: Wed, 27 Aug 2025 18:22:27 +0400
Subject: [PATCH 8/8] util functions fix

---
 .../org/jetbrains/kotlinx/dataframe/api/any.kt      |  1 +
 .../org/jetbrains/kotlinx/dataframe/api/between.kt  |  2 +-
 .../org/jetbrains/kotlinx/dataframe/api/tail.kt     | 11 ++++++++---
 .../kotlinx/dataframe/util/deprecationMessages.kt   |  3 ---
 .../kotlinx/dataframe/samples/api/Create.kt         | 13 -------------
 .../kotlinx/dataframe/examples/plugin/Main.kt       |  2 --
 6 files changed, 10 insertions(+), 22 deletions(-)

diff --git a/core/src/main/kotlin/org/jetbrains/kotlinx/dataframe/api/any.kt b/core/src/main/kotlin/org/jetbrains/kotlinx/dataframe/api/any.kt
index 0c021125f4..1f7902f5d2 100644
--- a/core/src/main/kotlin/org/jetbrains/kotlinx/dataframe/api/any.kt
+++ b/core/src/main/kotlin/org/jetbrains/kotlinx/dataframe/api/any.kt
@@ -41,6 +41,7 @@ public fun <T> DataColumn<T>.any(predicate: Predicate<T>): Boolean = values.any(
  * @param predicate A [RowFilter] lambda that takes a [DataRow] (as both `this` and `it`)
  * and returns `true` if the row should be considered a match.
  * @return `true` if at least one row satisfies the [predicate], `false` otherwise.
+ * @see [DataFrame.all]
  */
 public inline fun <T> DataFrame<T>.any(predicate: RowFilter<T>): Boolean = rows().any { predicate(it, it) }
 
diff --git a/core/src/main/kotlin/org/jetbrains/kotlinx/dataframe/api/between.kt b/core/src/main/kotlin/org/jetbrains/kotlinx/dataframe/api/between.kt
index 6390a082bb..4280f67d3f 100644
--- a/core/src/main/kotlin/org/jetbrains/kotlinx/dataframe/api/between.kt
+++ b/core/src/main/kotlin/org/jetbrains/kotlinx/dataframe/api/between.kt
@@ -7,7 +7,7 @@ import org.jetbrains.kotlinx.dataframe.impl.between
 
 /**
  * Returns a [DataColumn] of [Boolean] values indicating whether each element
- * lies between [left] and [right].
+ * in this column lies between [left] and [right].
  *
  * If [includeBoundaries] is `true` (default), values equal to [left] or [right] are also considered in range.
  *
diff --git a/core/src/main/kotlin/org/jetbrains/kotlinx/dataframe/api/tail.kt b/core/src/main/kotlin/org/jetbrains/kotlinx/dataframe/api/tail.kt
index c2b652e977..c775970e10 100644
--- a/core/src/main/kotlin/org/jetbrains/kotlinx/dataframe/api/tail.kt
+++ b/core/src/main/kotlin/org/jetbrains/kotlinx/dataframe/api/tail.kt
@@ -1,12 +1,17 @@
 package org.jetbrains.kotlinx.dataframe.api
 
 import org.jetbrains.kotlinx.dataframe.DataFrame
-import org.jetbrains.kotlinx.dataframe.util.TAIL
-import org.jetbrains.kotlinx.dataframe.util.TAIL_REPLACE
 
 // region DataFrame
 
-@Deprecated(TAIL, ReplaceWith(TAIL_REPLACE), DeprecationLevel.ERROR)
+/**
+ * Returns a DataFrame containing the last [numRows] rows.
+ *
+ * Equivalent to [takeLast].
+ *
+ * @param numRows The number of rows to return from the end of the DataFrame. Defaults to 5.
+ * @return A DataFrame containing the last [numRows] rows.
+ */
 public fun <T> DataFrame<T>.tail(numRows: Int = 5): DataFrame<T> = takeLast(numRows)
 
 // endregion
diff --git a/core/src/main/kotlin/org/jetbrains/kotlinx/dataframe/util/deprecationMessages.kt b/core/src/main/kotlin/org/jetbrains/kotlinx/dataframe/util/deprecationMessages.kt
index 4a7dcb4b88..21d5e44b40 100644
--- a/core/src/main/kotlin/org/jetbrains/kotlinx/dataframe/util/deprecationMessages.kt
+++ b/core/src/main/kotlin/org/jetbrains/kotlinx/dataframe/util/deprecationMessages.kt
@@ -139,9 +139,6 @@ internal const val COL_TYPE_INSTANT =
     "kotlinx.datetime.Instant is deprecated in favor of kotlin.time.Instant. Either migrate to kotlin.time.Instant and use ColType.StdlibInstant or use ColType.DeprecatedInstant. $MESSAGE_1_0 and migrated to kotlin.time.Instant in 1.1."
 internal const val COL_TYPE_INSTANT_REPLACE = "ColType.DeprecatedInstant"
 
-internal const val TAIL = "This function will be removed in favor of `takeLast()`. $MESSAGE_1_0"
-internal const val TAIL_REPLACE = "this.takeLast(numRows)"
-
 // endregion
 
 // region WARNING in 1.0, ERROR in 1.1
diff --git a/core/src/test/kotlin/org/jetbrains/kotlinx/dataframe/samples/api/Create.kt b/core/src/test/kotlin/org/jetbrains/kotlinx/dataframe/samples/api/Create.kt
index 9dfa164049..860c48062e 100644
--- a/core/src/test/kotlin/org/jetbrains/kotlinx/dataframe/samples/api/Create.kt
+++ b/core/src/test/kotlin/org/jetbrains/kotlinx/dataframe/samples/api/Create.kt
@@ -78,19 +78,6 @@ class Create : TestBase() {
         // SampleEnd
     }
 
-    // Not used anymore
-    /*@Test
-    @TransformDataFrameExpressions
-    fun columnAccessorToColumn() {
-        // SampleStart
-        val age by column<Int>()
-        val ageCol1 = age.withValues(15, 20)
-        val ageCol2 = age.withValues(1..10)
-        // SampleEnd
-
-        ageCol2.size() shouldBe 10
-    }*/
-
     @Test
     @TransformDataFrameExpressions
     fun columnAccessorMap() {
diff --git a/examples/kotlin-dataframe-plugin-example/src/main/kotlin/org/jetbrains/kotlinx/dataframe/examples/plugin/Main.kt b/examples/kotlin-dataframe-plugin-example/src/main/kotlin/org/jetbrains/kotlinx/dataframe/examples/plugin/Main.kt
index 562d700db3..a1ed3145fa 100644
--- a/examples/kotlin-dataframe-plugin-example/src/main/kotlin/org/jetbrains/kotlinx/dataframe/examples/plugin/Main.kt
+++ b/examples/kotlin-dataframe-plugin-example/src/main/kotlin/org/jetbrains/kotlinx/dataframe/examples/plugin/Main.kt
@@ -6,11 +6,9 @@ import org.jetbrains.kotlinx.dataframe.api.add
 import org.jetbrains.kotlinx.dataframe.api.convert
 import org.jetbrains.kotlinx.dataframe.api.convertTo
 import org.jetbrains.kotlinx.dataframe.api.filter
-import org.jetbrains.kotlinx.dataframe.api.insert
 import org.jetbrains.kotlinx.dataframe.api.into
 import org.jetbrains.kotlinx.dataframe.api.rename
 import org.jetbrains.kotlinx.dataframe.api.renameToCamelCase
-import org.jetbrains.kotlinx.dataframe.api.under
 import org.jetbrains.kotlinx.dataframe.api.with
 import org.jetbrains.kotlinx.dataframe.io.readCsv
 import org.jetbrains.kotlinx.dataframe.io.writeCsv