Reject nils for quartils computations

Author: jecisc

src/DataFrame-Tests/DataSeriesTest.class.st

@@ -2015,6 +2015,16 @@ DataSeriesTest >> testStatsQuartile [
 	self assert: (series quartile: 4) equals: 20.
 ]
 
+{ #category : #statistics }
+DataSeriesTest >> testStatsQuartileWithNil [
+	series atIndex: 2 put: nil.
+	self assert: (series quartile: 0) equals: 3.
+	self assert: (series quartile: 1) equals: 8.
+	self assert: (series quartile: 2) equals: 9.
+	self assert: (series quartile: 3) equals: 15.
+	self assert: (series quartile: 4) equals: 20.
+]
+
 { #category : #statistics }
 DataSeriesTest >> testStatsRange [
 

src/DataFrame/DataSeries.class.st

@@ -401,7 +401,7 @@ DataSeries >> initialize: aCapacity [
 
 { #category : #statistics }
 DataSeries >> interquartileRange [
-	^ self thirdQuartile - self firstQuartile 
+	^ self thirdQuartile - self firstQuartile
 ]
 
 { #category : #'categorical-numerical' }
@@ -479,14 +479,14 @@ DataSeries >> ninth [
 
 { #category : #statistics }
 DataSeries >> quantile: aNumber [
+
 	| sortedSeries index |
-	sortedSeries := self sorted.
-	
-	aNumber = 0
-		ifTrue: [ ^ sortedSeries first ].
-	
+	sortedSeries := self withoutNils sorted.
+
+	aNumber = 0 ifTrue: [ ^ sortedSeries first ].
+
 	index := (sortedSeries size * (aNumber / 100)) ceiling.
-	^ sortedSeries atIndex: index.
+	^ sortedSeries atIndex: index
 ]
 
 { #category : #statistics }
@@ -856,6 +856,12 @@ DataSeries >> withSeries: otherDataSeries collect: twoArgBlock [
 	^ result
 ]
 
+{ #category : #private }
+DataSeries >> withoutNils [
+
+	^ self reject: #isNil
+]
+
 { #category : #statistics }
 DataSeries >> zerothQuartile [
 	^ self quartile: 0