init research

dataframe/plugins/kotlin-dataframe/testData/box/perRowCol.kt

@@ -0,0 +1,10 @@
+import org.jetbrains.kotlinx.dataframe.*
+import org.jetbrains.kotlinx.dataframe.annotations.*
+import org.jetbrains.kotlinx.dataframe.api.*
+import org.jetbrains.kotlinx.dataframe.io.*
+
+fun box(): String {
+    val df = dataFrameOf("a")(123).convert { a }.perRowCol { row, col -> "" }
+    val value: String = df.a[0]
+    return "OK"
+}