[SPARK-24408][SQL][DOC] Move abs, bitwiseNOT, isnan, nanvl functions …

…to math_funcs group

sql/core/src/main/scala/org/apache/spark/sql/functions.scala

@@ -1031,14 +1031,6 @@ object functions {
   // Non-aggregate functions
   //////////////////////////////////////////////////////////////////////////////////////////////
 
-  /**
-   * Computes the absolute value.
-   *
-   * @group normal_funcs
-   * @since 1.3.0
-   */
-  def abs(e: Column): Column = withExpr { Abs(e.expr) }
-
   /**
    * Creates a new array column. The input columns must all have the same data type.
    *
@@ -1107,14 +1099,6 @@ object functions {
    */
   def input_file_name(): Column = withExpr { InputFileName() }
 
-  /**
-   * Return true iff the column is NaN.
-   *
-   * @group normal_funcs
-   * @since 1.6.0
-   */
-  def isnan(e: Column): Column = withExpr { IsNaN(e.expr) }
-
   /**
    * Return true iff the column is null.
    *
@@ -1164,16 +1148,6 @@ object functions {
    */
   def monotonically_increasing_id(): Column = withExpr { MonotonicallyIncreasingID() }
 
-  /**
-   * Returns col1 if it is not NaN, or col2 if col1 is NaN.
-   *
-   * Both inputs should be floating point columns (DoubleType or FloatType).
-   *
-   * @group normal_funcs
-   * @since 1.5.0
-   */
-  def nanvl(col1: Column, col2: Column): Column = withExpr { NaNvl(col1.expr, col2.expr) }
-
   /**
    * Unary minus, i.e. negate the expression.
    * {{{
@@ -1324,14 +1298,6 @@ object functions {
     CaseWhen(Seq((condition.expr, lit(value).expr)))
   }
 
-  /**
-   * Computes bitwise NOT.
-   *
-   * @group normal_funcs
-   * @since 1.4.0
-   */
-  def bitwiseNOT(e: Column): Column = withExpr { BitwiseNot(e.expr) }
-
   /**
    * Parses the expression string into the column that it represents, similar to
    * [[Dataset#selectExpr]].
@@ -1353,6 +1319,14 @@ object functions {
   // Math Functions
   //////////////////////////////////////////////////////////////////////////////////////////////
 
+  /**
+    * Computes the absolute value of a numeric value.
+    *
+    * @group math_funcs
+    * @since 1.3.0
+    */
+  def abs(e: Column): Column = withExpr { Abs(e.expr) }
+
   /**
    * @return inverse cosine of `e` in radians, as if computed by `java.lang.Math.acos`
    *
@@ -1532,6 +1506,14 @@ object functions {
    */
   def bin(columnName: String): Column = bin(Column(columnName))
 
+  /**
+    * Computes bitwise NOT (~) of a number.
+    *
+    * @group math_funcs
+    * @since 1.4.0
+    */
+  def bitwiseNOT(e: Column): Column = withExpr { BitwiseNot(e.expr) }
+
   /**
    * Computes the cube-root of the given value.
    *
@@ -1696,6 +1678,26 @@ object functions {
    */
   def hex(column: Column): Column = withExpr { Hex(column.expr) }
 
+  /**
+    * Return true iff the column is NaN.
+    *
+    * Both inputs should be floating point columns (DoubleType or FloatType).
+    *
+    * @group math_funcs
+    * @since 1.6.0
+    */
+  def isnan(e: Column): Column = withExpr { IsNaN(e.expr) }
+
+  /**
+    * Returns col1 if it is not NaN, or col2 if col1 is NaN.
+    *
+    * Both inputs should be floating point columns (DoubleType or FloatType).
+    *
+    * @group math_funcs
+    * @since 1.5.0
+    */
+  def nanvl(col1: Column, col2: Column): Column = withExpr { NaNvl(col1.expr, col2.expr) }
+
   /**
    * Inverse of hex. Interprets each pair of characters as a hexadecimal number
    * and converts to the byte representation of number.