From 6c30299e360dcc1264561161557294ee1db014e2 Mon Sep 17 00:00:00 2001
From: John Shahid <jvshahid@gmail.com>
Date: Fri, 18 Oct 2013 13:29:57 -0400
Subject: [PATCH] combine median and percentile.

---
 src/engine/aggregator.go | 107 +++------------------------------------
 1 file changed, 6 insertions(+), 101 deletions(-)

diff --git a/src/engine/aggregator.go b/src/engine/aggregator.go
index 46bf0af953..8db76d4a84 100644
--- a/src/engine/aggregator.go
+++ b/src/engine/aggregator.go
@@ -221,112 +221,15 @@ func NewMeanAggregator(_ *parser.Query, value *parser.Value) (Aggregator, error)
 		counts:    make(map[string]map[interface{}]int),
 	}, nil
 }
-
-//
-// Median Aggregator
-//
-
-type MedianAggregator struct {
-	fieldName    string
-	fieldIndex   int
-	fieldType    protocol.FieldDefinition_Type
-	int_values   map[string]map[interface{}][]int64
-	float_values map[string]map[interface{}][]float64
-}
-
-func (self *MedianAggregator) AggregatePoint(series string, group interface{}, p *protocol.Point) error {
-	switch self.fieldType {
-	case protocol.FieldDefinition_INT64:
-		int_values := self.int_values[series]
-		if int_values == nil {
-			int_values = make(map[interface{}][]int64)
-			self.int_values[series] = int_values
-		}
-
-		points := int_values[group]
-		if points == nil {
-			points = []int64{}
-		}
-
-		points = append(points, *p.Values[self.fieldIndex].Int64Value)
-		int_values[group] = points
-	case protocol.FieldDefinition_DOUBLE:
-		float_values := self.float_values[series]
-		if float_values == nil {
-			float_values = make(map[interface{}][]float64)
-			self.float_values[series] = float_values
-		}
-
-		points := float_values[group]
-		if points == nil {
-			points = make([]float64, 0)
-		}
-
-		points = append(points, *p.Values[self.fieldIndex].DoubleValue)
-		float_values[group] = points
-	default:
-		return common.NewQueryError(common.InvalidArgument, fmt.Sprintf("Field %s has invalid type %v", self.fieldName, self.fieldType))
-	}
-
-	return nil
-}
-
-func (self *MedianAggregator) ColumnName() string {
-	return "median"
-}
-
-func (self *MedianAggregator) ColumnType() protocol.FieldDefinition_Type {
-	return self.fieldType
-}
-
-func (self *MedianAggregator) GetValue(series string, group interface{}) []*protocol.FieldValue {
-	returnValues := []*protocol.FieldValue{}
-
-	switch self.fieldType {
-	case protocol.FieldDefinition_INT64:
-		SortInt64(self.int_values[series][group])
-		length := len(self.int_values[series][group])
-		index := int(math.Floor(float64(length)*0.5+0.5)) - 1
-		point := int64(self.int_values[series][group][index])
-		returnValues = append(returnValues, &protocol.FieldValue{Int64Value: &point})
-	case protocol.FieldDefinition_DOUBLE:
-		sort.Float64s(self.float_values[series][group])
-		length := len(self.float_values[series][group])
-		index := int(math.Floor(float64(length)*0.5+0.5)) - 1
-		point := self.float_values[series][group][index]
-		returnValues = append(returnValues, &protocol.FieldValue{DoubleValue: &point})
-	}
-	return returnValues
-}
-
-func (self *MedianAggregator) InitializeFieldsMetadata(series *protocol.Series) error {
-	for idx, field := range series.Fields {
-		if *field.Name == self.fieldName {
-			self.fieldIndex = idx
-			self.fieldType = *field.Type
-
-			switch self.fieldType {
-			case protocol.FieldDefinition_INT64,
-				protocol.FieldDefinition_DOUBLE:
-				// that's fine
-			default:
-				return common.NewQueryError(common.InvalidArgument, fmt.Sprintf("Field %s has invalid type %v", self.fieldName, self.fieldType))
-			}
-
-			return nil
-		}
-	}
-
-	return common.NewQueryError(common.InvalidArgument, fmt.Sprintf("Unknown column name %s", self.fieldName))
-}
-
 func NewMedianAggregator(_ *parser.Query, value *parser.Value) (Aggregator, error) {
 	if len(value.Elems) != 1 {
 		return nil, common.NewQueryError(common.WrongNumberOfArguments, "function median() requires exactly one argument")
 	}
 
-	return &MedianAggregator{
+	return &PercentileAggregator{
+		functionName: "median",
 		fieldName:    value.Elems[0].Name,
+		percentile:   50.0,
 		int_values:   make(map[string]map[interface{}][]int64),
 		float_values: make(map[string]map[interface{}][]float64),
 	}, nil
@@ -337,6 +240,7 @@ func NewMedianAggregator(_ *parser.Query, value *parser.Value) (Aggregator, erro
 //
 
 type PercentileAggregator struct {
+	functionName string
 	fieldName    string
 	fieldIndex   int
 	fieldType    protocol.FieldDefinition_Type
@@ -383,7 +287,7 @@ func (self *PercentileAggregator) AggregatePoint(series string, group interface{
 }
 
 func (self *PercentileAggregator) ColumnName() string {
-	return "percentile"
+	return self.functionName
 }
 
 func (self *PercentileAggregator) ColumnType() protocol.FieldDefinition_Type {
@@ -443,6 +347,7 @@ func NewPercentileAggregator(_ *parser.Query, value *parser.Value) (Aggregator,
 	}
 
 	return &PercentileAggregator{
+		functionName: "percentile",
 		fieldName:    value.Elems[0].Name,
 		percentile:   percentile,
 		int_values:   make(map[string]map[interface{}][]int64),