init research

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

@@ -0,0 +1,16 @@
+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" to listOf("1", "1", "2", "3", "1", "4", "1"))
+    val counts = df.valueCounts(ascending = true, sort = false, dropNA = false) { a }
+    counts.a
+    counts.count
+
+    val counts1 = df.valueCounts(resultColumn = "a") { a }
+    val col: DataColumn<String> = counts1.a
+    val col1: DataColumn<Int> counts1.a1
+    return "OK"
+}