data.groupBy("gender").agg(count($"age"),max($"age").as("maxAge"), avg($"age").as("avgAge")).show
+------+----------+------+------+
|gender|count(age)|maxAge|avgAge|
+------+----------+------+------+
|female| 5| 32.0| 29.0|
| male| 5| 57.0| 39.0|
+------+----------+------+------+
data.groupBy("gender").agg("age"->"count","age" -> "max", "age" -> "avg").show
+------+----------+--------+--------+
|gender|count(age)|max(age)|avg(age)|
+------+----------+--------+--------+
|female| 5| 32.0| 29.0|
| male| 5| 57.0| 39.0|
+------+----------+--------+--------+