init research

dataframe/plugins/kotlin-dataframe/testData/box/csDsl/take.kt

@@ -0,0 +1,29 @@
+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 {
+    compareSchemas(
+        df.select { name.firstName },
+        df.select { name.takeCols(1) },
+    )
+
+    compareSchemas(
+        df.select { name.lastName },
+        df.select { name.takeLastCols(1) },
+    )
+
+    compareSchemas(
+        df.select { name and age and city },
+        df.select { take(3) },
+        df.select { all().take(3) },
+    )
+
+    compareSchemas(
+        df.select { city and weight and isHappy },
+        df.select { all().takeLast(3) },
+        df.select { takeLast(3) },
+    )
+    return "OK"
+}