Add toDataFrame(columnName) overload

Author: koperagen

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

@@ -202,6 +202,13 @@ public abstract class CreateDataFrameDsl<T> : TraversePropertiesDsl {
     public abstract operator fun String.invoke(builder: CreateDataFrameDsl<T>.() -> Unit)
 }
 
+@Refine
+@Interpretable("ToDataFrameColumn")
+public inline fun <reified T> Iterable<T>.toDataFrame(columnName: String): DataFrame<*> =
+    toDataFrame {
+        columnName from { it }
+    }
+
 // endregion
 
 // region toDataFrame overloads for built-in types
@@ -304,6 +311,8 @@ public interface ValueProperty<T> {
     public val value: T
 }
 
+// endregion
+
 // region Create DataFrame from Map
 
 public fun Map<String, Iterable<Any?>>.toDataFrame(): AnyFrame =

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

@@ -11,6 +11,7 @@ import org.jetbrains.kotlinx.dataframe.kind
 import org.jetbrains.kotlinx.dataframe.type
 import org.junit.Ignore
 import org.junit.Test
+import java.io.File
 import kotlin.reflect.KProperty
 import kotlin.reflect.typeOf
 
@@ -452,4 +453,11 @@ class CreateDataFrameTests {
             df.participants[0].city
         }
     }
+
+    @Test
+    fun toDataFrameColumn() {
+        val files = listOf(File("data.csv"))
+        val df = files.toDataFrame(columnName = "files")
+        df["files"][0] shouldBe File("data.csv")
+    }
 }

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

@@ -31,6 +31,7 @@ import org.jetbrains.kotlinx.dataframe.explainer.TransformDataFrameExpressions
 import org.jetbrains.kotlinx.dataframe.kind
 import org.jetbrains.kotlinx.dataframe.type
 import org.junit.Test
+import java.io.File
 import kotlin.reflect.typeOf
 
 class Create : TestBase() {
@@ -456,4 +457,13 @@ class Create : TestBase() {
         peek(dataFrameOf(col), dataFrameOf(col))
         // SampleEnd
     }
+
+    @Test
+    @TransformDataFrameExpressions
+    fun toDataFrameColumn() {
+        // SampleStart
+        val files = listOf(File("data.csv"), File("data1.csv"))
+        val df = files.toDataFrame(columnName = "data")
+        // SampleEnd
+    }
 }