Merge pull request #617 from Kotlin/pivot-then

then operation in pivot column selection DSL inside aggregate

Author: koperagen

core/generated-sources/src/main/kotlin/org/jetbrains/kotlinx/dataframe/api/pivot.kt

@@ -148,7 +148,7 @@ public fun <G> GroupBy<*, G>.pivotCounts(vararg columns: KProperty<*>, inward: B
 
 // region pivot
 
-public fun <T> AggregateGroupedDsl<T>.pivot(inward: Boolean = true, columns: ColumnsSelector<T, *>): PivotGroupBy<T> =
+public fun <T> AggregateGroupedDsl<T>.pivot(inward: Boolean = true, columns: PivotColumnsSelector<T, *>): PivotGroupBy<T> =
     PivotInAggregateImpl(this, columns, inward)
 
 public fun <T> AggregateGroupedDsl<T>.pivot(vararg columns: String, inward: Boolean = true): PivotGroupBy<T> =

core/generated-sources/src/main/kotlin/org/jetbrains/kotlinx/dataframe/impl/aggregation/PivotInAggregateImpl.kt

@@ -4,14 +4,15 @@ import org.jetbrains.kotlinx.dataframe.ColumnsSelector
 import org.jetbrains.kotlinx.dataframe.DataFrame
 import org.jetbrains.kotlinx.dataframe.aggregation.AggregateBody
 import org.jetbrains.kotlinx.dataframe.aggregation.AggregateGroupedDsl
+import org.jetbrains.kotlinx.dataframe.api.PivotColumnsSelector
 import org.jetbrains.kotlinx.dataframe.api.PivotGroupBy
 import org.jetbrains.kotlinx.dataframe.impl.api.AggregatedPivot
 import org.jetbrains.kotlinx.dataframe.impl.api.aggregatePivot
 import org.jetbrains.kotlinx.dataframe.impl.columns.toColumnSet
 
 internal data class PivotInAggregateImpl<T>(
     val aggregator: AggregateGroupedDsl<T>,
-    val columns: ColumnsSelector<T, *>,
+    val columns: PivotColumnsSelector<T, *>,
     val inward: Boolean?,
     val default: Any? = null
 ) : PivotGroupBy<T>, AggregatableInternal<T> {

core/generated-sources/src/test/kotlin/org/jetbrains/kotlinx/dataframe/api/pivot.kt

@@ -153,4 +153,19 @@ class PivotTests {
                 1, -1, 5
             )
     }
+
+    @Test
+    fun `pivot then in aggregate`() {
+        val df = dataFrameOf(
+            "category1" to List(12) { it % 3 },
+            "category2" to List(12) { "category2_${it % 2}" },
+            "category3" to List(12) { "category3_${it % 5}" },
+            "value" to List(12) { it }
+        )
+
+        val df1 = df.groupBy("category1").aggregate {
+            pivot { "category2" then "category3" }.count()
+        }
+        df1 shouldBe df.pivot { "category2" then "category3" }.groupBy("category1").count()
+    }
 }

core/src/main/kotlin/org/jetbrains/kotlinx/dataframe/api/pivot.kt

@@ -148,7 +148,7 @@ public fun <G> GroupBy<*, G>.pivotCounts(vararg columns: KProperty<*>, inward: B
 
 // region pivot
 
-public fun <T> AggregateGroupedDsl<T>.pivot(inward: Boolean = true, columns: ColumnsSelector<T, *>): PivotGroupBy<T> =
+public fun <T> AggregateGroupedDsl<T>.pivot(inward: Boolean = true, columns: PivotColumnsSelector<T, *>): PivotGroupBy<T> =
     PivotInAggregateImpl(this, columns, inward)
 
 public fun <T> AggregateGroupedDsl<T>.pivot(vararg columns: String, inward: Boolean = true): PivotGroupBy<T> =

core/src/main/kotlin/org/jetbrains/kotlinx/dataframe/impl/aggregation/PivotInAggregateImpl.kt

@@ -4,14 +4,15 @@ import org.jetbrains.kotlinx.dataframe.ColumnsSelector
 import org.jetbrains.kotlinx.dataframe.DataFrame
 import org.jetbrains.kotlinx.dataframe.aggregation.AggregateBody
 import org.jetbrains.kotlinx.dataframe.aggregation.AggregateGroupedDsl
+import org.jetbrains.kotlinx.dataframe.api.PivotColumnsSelector
 import org.jetbrains.kotlinx.dataframe.api.PivotGroupBy
 import org.jetbrains.kotlinx.dataframe.impl.api.AggregatedPivot
 import org.jetbrains.kotlinx.dataframe.impl.api.aggregatePivot
 import org.jetbrains.kotlinx.dataframe.impl.columns.toColumnSet
 
 internal data class PivotInAggregateImpl<T>(
     val aggregator: AggregateGroupedDsl<T>,
-    val columns: ColumnsSelector<T, *>,
+    val columns: PivotColumnsSelector<T, *>,
     val inward: Boolean?,
     val default: Any? = null
 ) : PivotGroupBy<T>, AggregatableInternal<T> {

core/src/test/kotlin/org/jetbrains/kotlinx/dataframe/api/pivot.kt

@@ -153,4 +153,19 @@ class PivotTests {
                 1, -1, 5
             )
     }
+
+    @Test
+    fun `pivot then in aggregate`() {
+        val df = dataFrameOf(
+            "category1" to List(12) { it % 3 },
+            "category2" to List(12) { "category2_${it % 2}" },
+            "category3" to List(12) { "category3_${it % 5}" },
+            "value" to List(12) { it }
+        )
+
+        val df1 = df.groupBy("category1").aggregate {
+            pivot { "category2" then "category3" }.count()
+        }
+        df1 shouldBe df.pivot { "category2" then "category3" }.groupBy("category1").count()
+    }
 }