From 9dc5e564ed00586598981ed961adf9739d199f16 Mon Sep 17 00:00:00 2001
From: CyrilFerlicot <cyril@ferlicot.me>
Date: Mon, 13 Mar 2023 15:50:24 +0100
Subject: [PATCH 1/4] Fix two random failing tests by using a random generator
 with a fixed seed

Fixes #298
---
 .../PMIterativeProcess.class.st               |  3 +-
 .../PMFunctionOptimizer.class.st              |  7 +-
 .../PMOneVariableFunctionOptimizer.class.st   | 84 ++++++++++++-------
 .../PMOptimizingBracketFinder.class.st        | 32 ++++---
 .../PMSimplexOptimizer.class.st               | 41 +++++----
 .../PMNumericalMethodsTestCase.class.st       |  4 +-
 6 files changed, 105 insertions(+), 66 deletions(-)

diff --git a/src/Math-Core-Process/PMIterativeProcess.class.st b/src/Math-Core-Process/PMIterativeProcess.class.st
index 827d374d9..0df1697e8 100644
--- a/src/Math-Core-Process/PMIterativeProcess.class.st
+++ b/src/Math-Core-Process/PMIterativeProcess.class.st
@@ -82,8 +82,7 @@ PMIterativeProcess >> initialize [
 	super initialize.
 
 	desiredPrecision := self class defaultPrecision.
-	maximumIterations := self class defaultMaximumIterations.
-	^ self
+	maximumIterations := self class defaultMaximumIterations
 ]
 
 { #category : #operation }
diff --git a/src/Math-Numerical/PMFunctionOptimizer.class.st b/src/Math-Numerical/PMFunctionOptimizer.class.st
index d27bfaf34..bd1067f96 100644
--- a/src/Math-Numerical/PMFunctionOptimizer.class.st
+++ b/src/Math-Numerical/PMFunctionOptimizer.class.st
@@ -60,9 +60,10 @@ PMFunctionOptimizer >> initialValue: aVector [
 
 { #category : #initialization }
 PMFunctionOptimizer >> initialize [
-		"Private"
-	bestPoints := SortedCollection sortBlock: [ :a :b | a betterThan: b].
-	^super initialize
+	"Private"
+
+	super initialize.
+	bestPoints := SortedCollection sortBlock: [ :a :b | a betterThan: b ]
 ]
 
 { #category : #initialization }
diff --git a/src/Math-Numerical/PMOneVariableFunctionOptimizer.class.st b/src/Math-Numerical/PMOneVariableFunctionOptimizer.class.st
index c4a4644a1..b97dee913 100644
--- a/src/Math-Numerical/PMOneVariableFunctionOptimizer.class.st
+++ b/src/Math-Numerical/PMOneVariableFunctionOptimizer.class.st
@@ -1,6 +1,9 @@
 Class {
 	#name : #PMOneVariableFunctionOptimizer,
 	#superclass : #PMFunctionOptimizer,
+	#instVars : [
+		'randomGenerator'
+	],
 	#classVars : [
 		'GoldenSection'
 	],
@@ -24,69 +27,86 @@ PMOneVariableFunctionOptimizer class >> goldenSection [
 { #category : #operation }
 PMOneVariableFunctionOptimizer >> computeInitialValues [
 
-	[ bestPoints size  > 3] whileTrue: [ bestPoints removeLast].
-	bestPoints size = 3
-		ifTrue: [ self hasBracketingPoints
-					ifFalse:[ bestPoints removeLast].
-				].
-	bestPoints size < 3
-		ifTrue: [ ( PMOptimizingBracketFinder forOptimizer: self) evaluate]
+	| finder |
+	[ bestPoints size > 3 ] whileTrue: [ bestPoints removeLast ].
+
+	bestPoints size = 3 ifTrue: [ self hasBracketingPoints ifFalse: [ bestPoints removeLast ] ].
+
+	bestPoints size < 3 ifFalse: [ ^ self ].
+
+	finder := PMOptimizingBracketFinder forOptimizer: self.
+	self randomGenerator ifNotNil: [ :generator | finder randomGenerator: generator ].
+	finder evaluate
 ]
 
 { #category : #information }
 PMOneVariableFunctionOptimizer >> computePrecision [
-	^self precisionOf: ( ( bestPoints at: 2) position - ( bestPoints at: 3) position) abs
-		   relativeTo: ( bestPoints at: 1) position abs
+
+	^ self precisionOf: ((bestPoints at: 2) position - (bestPoints at: 3) position) abs relativeTo: (bestPoints at: 1) position abs
 ]
 
 { #category : #operation }
 PMOneVariableFunctionOptimizer >> evaluateIteration [
+
 	self addPointAt: self nextXValue.
 	bestPoints removeAt: self indexOfOuterPoint.
-	^self computePrecision
+	^ self computePrecision
 ]
 
 { #category : #information }
 PMOneVariableFunctionOptimizer >> hasBracketingPoints [
-		"Private"
+	"Private"
+
 	| x1 |
-	x1 := ( bestPoints at: 1) position.
-	^( ( bestPoints at: 2) position - x1) * (( bestPoints at: 3) position - x1) < 0
+	x1 := (bestPoints at: 1) position.
+	^ (bestPoints at: 2) position - x1 * ((bestPoints at: 3) position - x1) < 0
 ]
 
 { #category : #information }
 PMOneVariableFunctionOptimizer >> indexOfOuterPoint [
-		"Private"
+	"Private"
+
 	| inferior superior x |
 	inferior := false.
 	superior := false.
 	x := bestPoints first position.
-	2 to: 4 do:
-		[ :n |
-		  ( bestPoints at: n) position < x
-				ifTrue: [ inferior
-							ifTrue: [ ^n].
-						  inferior := true.
-						]
-				ifFalse:[ superior
-							ifTrue: [ ^n].
-						  superior := true.
-						].
-		]
+	2 to: 4 do: [ :n |
+		(bestPoints at: n) position < x
+			ifTrue: [
+				inferior ifTrue: [ ^ n ].
+				inferior := true ]
+			ifFalse: [
+				superior ifTrue: [ ^ n ].
+				superior := true ] ]
 ]
 
 { #category : #information }
 PMOneVariableFunctionOptimizer >> nextXValue [
 	"Private"
+
 	| d3 d2 x1 |
-	x1 := ( bestPoints at: 1) position.
-	d2 := ( bestPoints at: 2) position - x1.
-	d3 := ( bestPoints at: 3) position - x1.
-	^( d3 abs > d2 abs ifTrue: [ d3]
-					   ifFalse:[ d2]) * self class goldenSection + x1
+	x1 := (bestPoints at: 1) position.
+	d2 := (bestPoints at: 2) position - x1.
+	d3 := (bestPoints at: 3) position - x1.
+	^ (d3 abs > d2 abs
+		   ifTrue: [ d3 ]
+		   ifFalse: [ d2 ]) * self class goldenSection + x1
+]
+
+{ #category : #accessing }
+PMOneVariableFunctionOptimizer >> randomGenerator [
+
+	^ randomGenerator
+]
+
+{ #category : #accessing }
+PMOneVariableFunctionOptimizer >> randomGenerator: anObject [
+
+	randomGenerator := anObject
 ]
 
 { #category : #transformation }
 PMOneVariableFunctionOptimizer >> reset [
-	[ bestPoints isEmpty] whileFalse: [ bestPoints removeLast]
+
+	bestPoints removeAll
 ]
diff --git a/src/Math-Numerical/PMOptimizingBracketFinder.class.st b/src/Math-Numerical/PMOptimizingBracketFinder.class.st
index 6ceb5fe4a..a7cc95e04 100644
--- a/src/Math-Numerical/PMOptimizingBracketFinder.class.st
+++ b/src/Math-Numerical/PMOptimizingBracketFinder.class.st
@@ -12,23 +12,20 @@ PMOptimizingBracketFinder class >> initialPoints: aSortedCollection function: aF
 
 { #category : #operation }
 PMOptimizingBracketFinder >> computeInitialValues [
-	| random |
-	random := Random new.
 
-	[ bestPoints size < 2 ] whileTrue: [
-		self addPointAt: random next ]
+	[ bestPoints size < 2 ] whileTrue: [ self addPointAt: self randomGenerator next ]
 ]
 
 { #category : #operation }
 PMOptimizingBracketFinder >> evaluateIteration [
+
 	| x1 x2 |
-	x1 := ( bestPoints at: 1) position.
-	x2 := ( bestPoints at: 2) position.
-	self addPointAt: ( x1 * 3 - ( x2 * 2)).
-	precision := ( x2 - x1) * ( ( bestPoints at: 3) position - x1).
-	self hasConverged
-		ifFalse:[ bestPoints removeLast].
-	^precision
+	x1 := (bestPoints at: 1) position.
+	x2 := (bestPoints at: 2) position.
+	self addPointAt: x1 * 3 - (x2 * 2).
+	precision := x2 - x1 * ((bestPoints at: 3) position - x1).
+	self hasConverged ifFalse: [ bestPoints removeLast ].
+	^ precision
 ]
 
 { #category : #operation }
@@ -36,15 +33,24 @@ PMOptimizingBracketFinder >> finalizeIterations [
 	result := bestPoints
 ]
 
+{ #category : #initialization }
+PMOptimizingBracketFinder >> initialize [
+
+	super initialize.
+	self randomGenerator: Random new
+]
+
 { #category : #initialization }
 PMOptimizingBracketFinder >> initializeForOptimizer: aFunctionOptimizer [
-		"Private"
+	"Private"
+
 	super initializeForOptimizer: aFunctionOptimizer.
 	bestPoints := aFunctionOptimizer bestPoints
 ]
 
 { #category : #initialization }
 PMOptimizingBracketFinder >> setInitialPoints: aSortedCollection [
-		"Private"
+	"Private"
+
 	bestPoints := aSortedCollection
 ]
diff --git a/src/Math-Numerical/PMSimplexOptimizer.class.st b/src/Math-Numerical/PMSimplexOptimizer.class.st
index 5e62cd7ac..63c9ad7fc 100644
--- a/src/Math-Numerical/PMSimplexOptimizer.class.st
+++ b/src/Math-Numerical/PMSimplexOptimizer.class.st
@@ -2,7 +2,8 @@ Class {
 	#name : #PMSimplexOptimizer,
 	#superclass : #PMFunctionOptimizer,
 	#instVars : [
-		'worstVector'
+		'worstVector',
+		'randomGenerator'
 	],
 	#category : #'Math-Numerical-Math-FunctionIterator'
 }
@@ -18,26 +19,24 @@ PMSimplexOptimizer >> buildInitialSimplex [
 	"Private"
 
 	| projectedFunction finder partialResult |
-	projectedFunction := PMProjectedOneVariableFunction
-				function: functionBlock.
+	projectedFunction := PMProjectedOneVariableFunction function: functionBlock.
 	finder := PMOneVariableFunctionOptimizer forOptimizer: self.
+	self randomGenerator ifNotNil: [ :generator | finder randomGenerator: generator ].
 	finder setFunction: projectedFunction.
-	[bestPoints size < (result size + 1)] whileTrue:
-			[projectedFunction
-				setArgument: result;
-				bumpIndex.
-			partialResult := finder
-						reset;
-						evaluate.
-			bestPoints add: (optimizingPointClass
-						vector: (projectedFunction argumentWith: partialResult)
-						function: functionBlock)]
+	[ bestPoints size < (result size + 1) ] whileTrue: [
+		projectedFunction
+			setArgument: result;
+			bumpIndex.
+		partialResult := finder
+			                 reset;
+			                 evaluate.
+		bestPoints add: (optimizingPointClass vector: (projectedFunction argumentWith: partialResult) function: functionBlock) ]
 ]
 
 { #category : #initialization }
 PMSimplexOptimizer >> computeInitialValues [
-	bestPoints
-		add: (optimizingPointClass vector: result function: functionBlock).
+
+	bestPoints add: (optimizingPointClass vector: result function: functionBlock).
 	self buildInitialSimplex.
 	worstVector := bestPoints removeLast position
 ]
@@ -106,3 +105,15 @@ PMSimplexOptimizer >> printOn: aStream [
 	aStream cr.
 	worstVector printOn: aStream
 ]
+
+{ #category : #accessing }
+PMSimplexOptimizer >> randomGenerator [
+
+	^ randomGenerator
+]
+
+{ #category : #accessing }
+PMSimplexOptimizer >> randomGenerator: anObject [
+
+	randomGenerator := anObject
+]
diff --git a/src/Math-Tests-Numerical/PMNumericalMethodsTestCase.class.st b/src/Math-Tests-Numerical/PMNumericalMethodsTestCase.class.st
index c2ae5b139..e76c622da 100644
--- a/src/Math-Tests-Numerical/PMNumericalMethodsTestCase.class.st
+++ b/src/Math-Tests-Numerical/PMNumericalMethodsTestCase.class.st
@@ -819,6 +819,7 @@ PMNumericalMethodsTestCase >> testOptimizeOneDimension [
 	| distr finder maximum |
 	distr := PMGammaDistribution shape: 2 scale: 5.
 	finder := PMOneVariableFunctionOptimizer maximizingFunction: distr.
+	finder randomGenerator: (Random seed: 42).
 	finder desiredPrecision: 1.0e-6.
 	maximum := finder evaluate.
 	self assert: (maximum - 5) abs < 1.0e-6.
@@ -848,8 +849,9 @@ PMNumericalMethodsTestCase >> testOptimizeSimplex [
 
 	| fBlock simplex educatedGuess result |
 	fBlock := [ :x | (x * x) negated exp ].
-	educatedGuess := #(0.5 1.0 0.5) asPMVector.
+	educatedGuess := #( 0.5 1.0 0.5 ) asPMVector.
 	simplex := PMSimplexOptimizer maximizingFunction: fBlock.
+	simplex randomGenerator: (Random seed: 42).
 	simplex initialValue: educatedGuess.
 	simplex desiredPrecision: 1.0e-6.
 	result := simplex evaluate.

From a2e4237a41c920cbdbf569f55e499c4909eba934 Mon Sep 17 00:00:00 2001
From: CyrilFerlicot <cyril@ferlicot.me>
Date: Mon, 13 Mar 2023 16:18:40 +0100
Subject: [PATCH 2/4] Fix a bunch of new random failing tests

FIxes #300
Fixes #306
---
 .../PMAnotherChromosomeManager.class.st       |  80 +++---
 .../PMAnotherGeneticOptimizer.class.st        |  13 +-
 .../PMErrorMinimizer.class.st                 |   5 +-
 src/Math-FunctionFit/PMFunctionFit.class.st   |   7 +-
 .../PMGeneralFunctionFit.class.st             |  83 +++---
 .../PMAnotherChromosomeManagerTest.class.st   | 248 ++++++++++--------
 .../PMAnotherGeneticOptimizerTest.class.st    | 153 +++++------
 .../PMGeneralFunctionFitTest.class.st         |  96 ++++---
 8 files changed, 377 insertions(+), 308 deletions(-)

diff --git a/src/Math-FunctionFit/PMAnotherChromosomeManager.class.st b/src/Math-FunctionFit/PMAnotherChromosomeManager.class.st
index 43dc664b6..8bda83a96 100644
--- a/src/Math-FunctionFit/PMAnotherChromosomeManager.class.st
+++ b/src/Math-FunctionFit/PMAnotherChromosomeManager.class.st
@@ -8,7 +8,8 @@ Class {
 	#instVars : [
 		'hammersley',
 		'rateOfLC',
-		'rateOfEir'
+		'rateOfEir',
+		'randomGenerator'
 	],
 	#classVars : [
 		'Primes'
@@ -33,28 +34,29 @@ PMAnotherChromosomeManager class >> integerDigitsFor: anInteger base: aBase [
 ]
 
 { #category : #utilities }
-PMAnotherChromosomeManager class >> numberOfHamersleyPoints: n dimension: d randomized: aBoolean [
+PMAnotherChromosomeManager class >> numberOfHamersleyPoints: n dimension: d randomGenerator: randomGenerator [
 	"a bit randomized "
-	| dist randomNumberGenerator |
+
+	| dist |
 	dist := 1.0 / n.
-	randomNumberGenerator := Random new.
-
-	^(1 to: n) collect: [ :number |
-		(1 to: d) collect: [ :dim |
-			(dim=1)
-				ifTrue: [ aBoolean
-					ifTrue: [ (number/n) - (randomNumberGenerator nextBetween: 0 and: dist) ]
-					ifFalse: [ number/n ] ]
-				ifFalse: [ |sum prime|
-					sum := 0.
-					prime := Primes at: dim - 1.
-
-					(self integerDigitsFor: number base: prime) reverse withIndexDo: [ :i :index |
-						sum := i / (prime raisedToInteger: index) + sum ].
-
-					aBoolean
-						ifTrue: [ sum + (randomNumberGenerator nextBetween: 0 and: dist) ]
-						ifFalse: [ sum ] ] ]].
+
+	^ (1 to: n) collect: [ :number |
+		  (1 to: d) collect: [ :dim |
+			  dim = 1
+				  ifTrue: [
+					  randomGenerator
+						  ifNotNil: [ number / n - (randomGenerator nextBetween: 0 and: dist) ]
+						  ifNil: [ number / n ] ]
+				  ifFalse: [
+					  | sum prime |
+					  sum := 0.
+					  prime := Primes at: dim - 1.
+
+					  (self integerDigitsFor: number base: prime) reverse withIndexDo: [ :i :index | sum := i / (prime raisedToInteger: index) + sum ].
+
+					  randomGenerator
+						  ifNotNil: [ sum + (randomGenerator nextBetween: 0 and: dist) ]
+						  ifNil: [ sum ] ] ] ]
 ]
 
 { #category : #'instance creation' }
@@ -108,14 +110,15 @@ PMAnotherChromosomeManager >> eirCrossover: aChromosome1 and: aChromosome2 [
 
 { #category : #initialization }
 PMAnotherChromosomeManager >> initialize [
-super initialize .
-populationSize :=100.
-hammersley :=true.
-rateOfEir :=0.16.
-rateOfLC:=0.29.
-rateOfMutation :=0.4.
-rateOfCrossover :=0.15.
-Primes  ifNil:[Primes :=Integer primesUpTo: 500].	"sufficient for up to 95 dimensions (parameters)"
+
+	super initialize.
+	populationSize := 100.
+	hammersley := true.
+	rateOfEir := 0.16.
+	rateOfLC := 0.29.
+	rateOfMutation := 0.4.
+	rateOfCrossover := 0.15.
+	Primes ifNil: [ Primes := Integer primesUpTo: 500 ] "sufficient for up to 95 dimensions (parameters)"
 ]
 
 { #category : #information }
@@ -205,6 +208,18 @@ PMAnotherChromosomeManager >> process: aChromosome1 and: aChromosome2 [
 								add: (self clone: aChromosome2)]]]]
 ]
 
+{ #category : #accessing }
+PMAnotherChromosomeManager >> randomGenerator [
+
+	^ randomGenerator
+]
+
+{ #category : #accessing }
+PMAnotherChromosomeManager >> randomGenerator: anObject [
+
+	randomGenerator := anObject
+]
+
 { #category : #private }
 PMAnotherChromosomeManager >> randomRangeAt: aPosition [
 ^(range at: aPosition )*(self smallDistribution )
@@ -212,9 +227,10 @@ PMAnotherChromosomeManager >> randomRangeAt: aPosition [
 
 { #category : #operation }
 PMAnotherChromosomeManager >> randomizePopulation [
-hammersley ifFalse: [^super randomizePopulation ].
-population :=self class numberOfHamersleyPoints: populationSize  dimension: origin size randomized: true.
-population := population collect: [:aChr| aChr *range +origin ]
+
+	hammersley ifFalse: [ ^ super randomizePopulation ].
+	population := self class numberOfHamersleyPoints: populationSize dimension: origin size randomGenerator: (self randomGenerator ifNil: [ Random new ]).
+	population := population collect: [ :aChr | aChr * range + origin ]
 ]
 
 { #category : #accessing }
diff --git a/src/Math-FunctionFit/PMAnotherGeneticOptimizer.class.st b/src/Math-FunctionFit/PMAnotherGeneticOptimizer.class.st
index 2e28abb6f..74cbe1198 100644
--- a/src/Math-FunctionFit/PMAnotherGeneticOptimizer.class.st
+++ b/src/Math-FunctionFit/PMAnotherGeneticOptimizer.class.st
@@ -95,7 +95,8 @@ PMAnotherGeneticOptimizer >> computePrecision: whateverData [  "can be changed t
 
 { #category : #operation }
 PMAnotherGeneticOptimizer >> evaluate [
-^Cursor wait showWhile: [super evaluate]
+
+	^ Cursor wait showWhile: [ super evaluate ]
 ]
 
 { #category : #operation }
@@ -129,12 +130,12 @@ statistics :=false
 
 { #category : #operation }
 PMAnotherGeneticOptimizer >> initializeIterations [
-	bestPoints size>=chromosomeManager populationSize
-		ifTrue: [bestPoints := bestPoints copyFrom: 1 to: (bestPoints size // 2 max: 1)].
+
+	bestPoints size >= chromosomeManager populationSize ifTrue: [ bestPoints := bestPoints copyFrom: 1 to: (bestPoints size // 2 max: 1) ].
 	super initializeIterations.
-	bestValueHistory:=OrderedCollection new.
-	worstValueHistory:=OrderedCollection new.
-	whateverHistory:=OrderedCollection new
+	bestValueHistory := OrderedCollection new.
+	worstValueHistory := OrderedCollection new.
+	whateverHistory := OrderedCollection new
 ]
 
 { #category : #operation }
diff --git a/src/Math-FunctionFit/PMErrorMinimizer.class.st b/src/Math-FunctionFit/PMErrorMinimizer.class.st
index 9b60de6af..2c36806ff 100644
--- a/src/Math-FunctionFit/PMErrorMinimizer.class.st
+++ b/src/Math-FunctionFit/PMErrorMinimizer.class.st
@@ -29,6 +29,7 @@ PMErrorMinimizer class >> function: aBlock data: aCollection [
 
 { #category : #accessing }
 PMErrorMinimizer >> maxFunction [
-"The number of data partitions used."
-^dataHolder size
+	"The number of data partitions used."
+
+	^ dataHolder size
 ]
diff --git a/src/Math-FunctionFit/PMFunctionFit.class.st b/src/Math-FunctionFit/PMFunctionFit.class.st
index a271ef4ac..9a76a2f72 100644
--- a/src/Math-FunctionFit/PMFunctionFit.class.st
+++ b/src/Math-FunctionFit/PMFunctionFit.class.st
@@ -43,7 +43,12 @@ PMFunctionFit >> accumulate: aWeightedPoint [
 
 { #category : #operation }
 PMFunctionFit >> computeChanges [
-	^[super computeChanges]on: PMSingularMatrixError  do:[:signal|signal messageText: 'singular error matrix, set better parameters'.signal pass]
+
+	^ [ super computeChanges ]
+		  on: PMSingularMatrixError
+		  do: [ :signal |
+			  signal messageText: 'singular error matrix, set better parameters'.
+			  signal pass ]
 ]
 
 { #category : #information }
diff --git a/src/Math-FunctionFit/PMGeneralFunctionFit.class.st b/src/Math-FunctionFit/PMGeneralFunctionFit.class.st
index 586011d56..4187f79f0 100644
--- a/src/Math-FunctionFit/PMGeneralFunctionFit.class.st
+++ b/src/Math-FunctionFit/PMGeneralFunctionFit.class.st
@@ -10,14 +10,14 @@ Class {
 	#name : #PMGeneralFunctionFit,
 	#superclass : #Object,
 	#instVars : [
-		'go',
 		'manager',
 		'errorFunction',
 		'result',
 		'firstResult',
 		'verbose',
 		'data',
-		'dataTruncated'
+		'dataTruncated',
+		'geneticOptimizer'
 	],
 	#category : #'Math-FunctionFit'
 }
@@ -92,27 +92,31 @@ self resetResult.
 
 { #category : #operation }
 PMGeneralFunctionFit >> evaluate [
-|ff|
-ff :=PMErrorMinimizer function: errorFunction.
-firstResult :=[ff evaluate .ff parameters]
-	onErrorDo: [ verbose ifTrue: [self inform: 'ErrorMinimizer was not successful']. nil].
-firstResult ifNotNil: [go addPointAt: firstResult] .
-firstResult := go evaluate .
-self errorType =#squared
-	ifTrue: [ff :=PMFunctionFit function: errorFunction function data: errorFunction data ].
-ff parameters: firstResult.
-ff desiredPrecision: PMFloatingPointMachine new machinePrecision.
-ff maximumIterations: 1000 .
-result:=[ff evaluate .ff parameters]
-			onErrorDo: [
-				verbose ifTrue: [self inform: 'last FunctionFit was not successful'].
-				ff result parameters].
-((errorFunction value: result) > (errorFunction value: firstResult)) ifTrue:[
-	ff:=result.
-	result :=firstResult.
-	firstResult :=ff.
-	verbose ifTrue: [self inform: 'first result was better than final result'  ] ].
-^result
+
+	| ff |
+	ff := PMErrorMinimizer function: errorFunction.
+	firstResult := [
+	               ff evaluate.
+	               ff parameters ] onErrorDo: [
+		               verbose ifTrue: [ self inform: 'ErrorMinimizer was not successful' ].
+		               nil ].
+	firstResult ifNotNil: [ geneticOptimizer addPointAt: firstResult ].
+	firstResult := geneticOptimizer evaluate.
+	self errorType = #squared ifTrue: [ ff := PMFunctionFit function: errorFunction function data: errorFunction data ].
+	ff parameters: firstResult.
+	ff desiredPrecision: PMFloatingPointMachine new machinePrecision.
+	ff maximumIterations: 1000.
+	result := [
+	          ff evaluate.
+	          ff parameters ] onErrorDo: [
+		          verbose ifTrue: [ self inform: 'last FunctionFit was not successful' ].
+		          ff result parameters ].
+	(errorFunction value: result) > (errorFunction value: firstResult) ifTrue: [
+		ff := result.
+		result := firstResult.
+		firstResult := ff.
+		verbose ifTrue: [ self inform: 'first result was better than final result' ] ].
+	^ result
 ]
 
 { #category : #operation }
@@ -165,16 +169,19 @@ errorFunction function: aBlock
 
 { #category : #initialization }
 PMGeneralFunctionFit >> initialize [
-super initialize .
-errorFunction :=PMErrorOfParameterFunction new.
-manager :=PMAnotherChromosomeManager new.
-manager populationSize: 50.
-go :=PMAnotherGeneticOptimizer minimizingFunction: errorFunction .
-go chromosomeManager: manager.
-go maximumIterations: 170.
-self errorType: #squared.
-verbose:=false.
-dataTruncated :=false
+
+	super initialize.
+	errorFunction := PMErrorOfParameterFunction new.
+	manager := PMAnotherChromosomeManager new
+		           populationSize: 50;
+		           yourself.
+	geneticOptimizer := (PMAnotherGeneticOptimizer minimizingFunction: errorFunction)
+		                    chromosomeManager: manager;
+		                    maximumIterations: 170;
+		                    yourself.
+	self errorType: #squared.
+	verbose := false.
+	dataTruncated := false
 ]
 
 { #category : #accessing }
@@ -186,7 +193,7 @@ PMGeneralFunctionFit >> manager [
 { #category : #accessing }
 PMGeneralFunctionFit >> maximumIterations: anInteger [
 "default is 170."
-go maximumIterations: anInteger.
+geneticOptimizer maximumIterations: anInteger.
 ^anInteger
 ]
 
@@ -207,7 +214,7 @@ manager range: (array2 - array1)
 { #category : #accessing }
 PMGeneralFunctionFit >> optimizer [
 "if you want to change parameters of AnotherGeneticOptimizer not directly available in GeneralFunctionFit"
-^go
+^geneticOptimizer
 ]
 
 { #category : #accessing }
@@ -221,7 +228,7 @@ manager populationSize: anInteger .
 { #category : #accessing }
 PMGeneralFunctionFit >> precision [
 "not really useful to look at, you might better look at #error"
-^go precision
+^geneticOptimizer precision
 ]
 
 { #category : #printing }
@@ -230,7 +237,7 @@ PMGeneralFunctionFit >> printOn: aStream [
 		nextPutAll: 'a ';
 		nextPutAll: self class name;
 		nextPut: $(;
-		print: go;
+		print: geneticOptimizer;
 		nextPutAll: ' with data of size: ';
 	  	print: data size .
 	 dataTruncated ifTrue:
@@ -272,7 +279,7 @@ self data: data
 PMGeneralFunctionFit >> resetResult [
 result :=nil.
 firstResult :=nil.
-go resetBestPoints
+geneticOptimizer resetBestPoints
 ]
 
 { #category : #accessing }
diff --git a/src/Math-Tests-FunctionFit/PMAnotherChromosomeManagerTest.class.st b/src/Math-Tests-FunctionFit/PMAnotherChromosomeManagerTest.class.st
index 9918eac11..50152d1c4 100644
--- a/src/Math-Tests-FunctionFit/PMAnotherChromosomeManagerTest.class.st
+++ b/src/Math-Tests-FunctionFit/PMAnotherChromosomeManagerTest.class.st
@@ -2,21 +2,21 @@ Class {
 	#name : #PMAnotherChromosomeManagerTest,
 	#superclass : #TestCase,
 	#instVars : [
-		'cm'
+		'chromosomeManager'
 	],
 	#category : #'Math-Tests-FunctionFit'
 }
 
 { #category : #running }
 PMAnotherChromosomeManagerTest >> setHammersleyTest: aBoolean [
-	cm useHammersley: aBoolean.
-	cm randomizePopulation.
-	self assert: cm isFullyPopulated.
-	self assert: (cm population anySatisfy: [ :g | g first > 1 ]).
-	self assert: (cm population anySatisfy: [ :g | g first < 1 ]).
-	self assert: (cm population anySatisfy: [ :g | g second < 2 ]).
-	self assert: (cm population anySatisfy: [ :g | g second > 3 ]).
-	cm population
+	chromosomeManager useHammersley: aBoolean.
+	chromosomeManager randomizePopulation.
+	self assert: chromosomeManager isFullyPopulated.
+	self assert: (chromosomeManager population anySatisfy: [ :g | g first > 1 ]).
+	self assert: (chromosomeManager population anySatisfy: [ :g | g first < 1 ]).
+	self assert: (chromosomeManager population anySatisfy: [ :g | g second < 2 ]).
+	self assert: (chromosomeManager population anySatisfy: [ :g | g second > 3 ]).
+	chromosomeManager population
 		do: [ :i |
 			self assert: i size equals: 2.
 			self assert: (i first between: 0 and: 2).
@@ -27,14 +27,15 @@ PMAnotherChromosomeManagerTest >> setHammersleyTest: aBoolean [
 PMAnotherChromosomeManagerTest >> setUp [
 
 	super setUp.
-	cm := PMAnotherChromosomeManager origin: #( 0 1 ) range: #( 2 3 )
+	chromosomeManager := PMAnotherChromosomeManager origin: #( 0 1 ) range: #( 2 3 ).
+	chromosomeManager randomGenerator: (Random seed: 42)
 ]
 
 { #category : #tests }
 PMAnotherChromosomeManagerTest >> testAccessing [
-	self assert: cm range equals: #(2 3).
-	self assert: cm populationSize equals: 100.
-	self deny: cm isFullyPopulated
+	self assert: chromosomeManager range equals: #(2 3).
+	self assert: chromosomeManager populationSize equals: 100.
+	self deny: chromosomeManager isFullyPopulated
 ]
 
 { #category : #tests }
@@ -42,7 +43,7 @@ PMAnotherChromosomeManagerTest >> testCrossOver [
 
 	| a |
 	1 to: 20 do: [ :i |
-		a := cm crossover: #( 1 2 3 ) and: #( 4 5 6 ).
+		a := chromosomeManager crossover: #( 1 2 3 ) and: #( 4 5 6 ).
 		1 to: 2 do: [ :index |
 			self assert: (#( 1 4 ) includes: (a at: index) first).
 			self assert: (#( 2 5 ) includes: ((a at: index) at: 2)).
@@ -58,7 +59,7 @@ PMAnotherChromosomeManagerTest >> testCrossOver [
 { #category : #tests }
 PMAnotherChromosomeManagerTest >> testEirCrossOver [
 |a|
-a :=(1 to: 200)collect: [:i| a:=cm eirCrossover: #(1.0 3.0) and: #(5.0 1.0).
+a :=(1 to: 200)collect: [:i| a:=chromosomeManager eirCrossover: #(1.0 3.0) and: #(5.0 1.0).
 		self assert: (((a at: 1)at:1) between: -1 and: 7).
 		self assert: (((a at: 1)at:2) between: 0 and: 4).
 		self assert: (((a at: 2)at:1) between: -1 and: 3).
@@ -72,8 +73,8 @@ self assert: (a anySatisfy: [:g|((g at: 2)at:1)<0]).
 self assert: (a anySatisfy: [:g|((g at: 2)at:1)>2]).
 self assert: (a anySatisfy: [:g|((g at: 2)at:2)<3]).
 self assert: (a anySatisfy: [:g|((g at: 2)at:2)>3]).
-self shouldnt: [a:=cm eirCrossover: #(1 -3) and: #(1 -3)] raise: Error.
-(1 to: 20)do: [:i| a:=cm eirCrossover: #(-1.0 -1) and: #(1 1.0).
+self shouldnt: [a:=chromosomeManager eirCrossover: #(1 -3) and: #(1 -3)] raise: Error.
+(1 to: 20)do: [:i| a:=chromosomeManager eirCrossover: #(-1.0 -1) and: #(1 1.0).
 		self assert: (((a at: 1)at:1) between: -2 and: 2).
 		self assert: (((a at: 1)at:2) between: -2 and: 2).
 		self assert: (((a at: 2)at:1) between: -2 and: 0).
@@ -100,34 +101,107 @@ PMAnotherChromosomeManagerTest >> testIntegerDigits [
 		equals: #(1 4 4)
 ]
 
+{ #category : #tests }
+PMAnotherChromosomeManagerTest >> testLineCrossOver [
+	| a |
+	1 to: 10 do: [ :i |
+		a := chromosomeManager lineCrossOver: #(-2 2) and: #(-4 4).
+		self assert: ((a at: 1) at: 2) equals: ((a at: 1) at: 1) negated.
+		self assert: ((a at: 2) at: 2) equals: ((a at: 2) at: 1) negated ]
+]
+
 { #category : #tests }
 PMAnotherChromosomeManagerTest >> testMutateProbabilistic [
-|a f s|
-a:=(1 to: 100)collect:  [:i| cm mutate: #(-4 4)].
-f:=a collect: [:i|i first].
-s :=f select:[:i|i>(-4)].
-self assert: (s size between: 15 and: 60).
-s :=f select:[:i|i=(-4)].
-self assert: (s size >20).
-s :=f select:[:i|i>(-3.8)or:[i<(-4.2)]].
-self assert: (s size between: 3 and: 20).
-s :=f select:[:i|i>(-3.9)or:[i<(-4.1)]].
-self assert: (s size between: 6 and: 50).
-
-f:=a collect: [:i|i second ].
-s :=f select:[:i|i>(4)].
-self assert: (s size between: 15 and: 60).
-s :=f select:[:i|i=(4)].
-self assert: (s size >20).
-s :=f select:[:i|i<(3.8)or:[i>(4.2)]].
-self assert: (s size between: 3 and: 20)
+
+	| a f s |
+	a := (1 to: 100) collect: [ :i | chromosomeManager mutate: #( -4 4 ) ].
+	f := a collect: [ :i | i first ].
+	s := f select: [ :i | i > -4 ].
+	self assert: (s size between: 15 and: 60).
+	s := f select: [ :i | i = -4 ].
+	self assert: s size > 20.
+	s := f select: [ :i | i > -3.8 or: [ i < -4.2 ] ].
+	self assert: (s size between: 3 and: 20).
+	s := f select: [ :i | i > -3.9 or: [ i < -4.1 ] ].
+	self assert: (s size between: 6 and: 50).
+
+	f := a collect: [ :i | i second ].
+	s := f select: [ :i | i > 4 ].
+	self assert: (s size between: 15 and: 60).
+	s := f select: [ :i | i = 4 ].
+	self assert: s size > 20.
+	s := f select: [ :i | i < 3.8 or: [ i > 4.2 ] ].
+	self assert: (s size between: 3 and: 20)
+]
+
+{ #category : #tests }
+PMAnotherChromosomeManagerTest >> testNumberOfHamersleyPoints [
+
+	| rand |
+	self
+		assert: (PMAnotherChromosomeManager numberOfHamersleyPoints: 9 dimension: 1 randomGenerator: nil)
+		equals: ((1 to: 9) collect: [ :i | Array with: i * (1 / 9) ]).
+	self assert: (PMAnotherChromosomeManager numberOfHamersleyPoints: 9 dimension: 4 randomGenerator: nil) equals: (OrderedCollection new
+			 add: (Array
+					  with: 1 / 9
+					  with: 1 / 2
+					  with: 1 / 3
+					  with: 1 / 5);
+			 add: (Array
+					  with: 2 / 9
+					  with: 1 / 4
+					  with: 2 / 3
+					  with: 2 / 5);
+			 add: (Array
+					  with: 1 / 3
+					  with: 3 / 4
+					  with: 1 / 9
+					  with: 3 / 5);
+			 add: (Array
+					  with: 4 / 9
+					  with: 1 / 8
+					  with: 4 / 9
+					  with: 4 / 5);
+			 add: (Array
+					  with: 5 / 9
+					  with: 5 / 8
+					  with: 7 / 9
+					  with: 1 / 25);
+			 add: (Array
+					  with: 2 / 3
+					  with: 3 / 8
+					  with: 2 / 9
+					  with: 6 / 25);
+			 add: (Array
+					  with: 7 / 9
+					  with: 7 / 8
+					  with: 5 / 9
+					  with: 11 / 25);
+			 add: (Array
+					  with: 8 / 9
+					  with: 1 / 16
+					  with: 8 / 9
+					  with: 16 / 25);
+			 add: (Array
+					  with: 1
+					  with: 9 / 16
+					  with: 1 / 27
+					  with: 21 / 25);
+			 asArray).
+	rand := (PMAnotherChromosomeManager numberOfHamersleyPoints: 3 dimension: 4 randomGenerator: nil)
+	        - (PMAnotherChromosomeManager numberOfHamersleyPoints: 3 dimension: 4 randomGenerator: (Random seed: 42)).
+	rand do: [ :i |
+		self assert: i first >= 0.
+		self assert: (i at: 2) < 0.
+		self assert: (i at: 3) < 0 ].
+	rand do: [ :i | i do: [ :j | j < (1 / 3) ] ]
 ]
 
 { #category : #tests }
 PMAnotherChromosomeManagerTest >> testPrint [
 |aStream  s|
 aStream :=ReadWriteStream with:''.
-cm printOn: aStream .
+chromosomeManager printOn: aStream .
 s :=aStream contents .
 self assert: (s includesSubstring: '#(0 1)').
 self assert: (s includesSubstring: '#(2 3)')
@@ -135,13 +209,13 @@ self assert: (s includesSubstring: '#(2 3)')
 
 { #category : #tests }
 PMAnotherChromosomeManagerTest >> testProcessand [
-	cm reset.
-	1 to: 60 do: [ :i | cm process: #(0 0) and: #(1 1) ].
-	self assert: (cm population select: [ :i | i = #(0 0) ]) size < 15.
-	self assert: (cm population select: [ :i | i = #(1 1) ]) size < 15.
-	self assert: (cm population select: [ :i | i = #(0 1) ]) size > 0.
-	self assert: (cm population select: [ :i | i = #(1 0) ]) size > 0.
-	self assert: cm population size equals: 120
+	chromosomeManager reset.
+	1 to: 60 do: [ :i | chromosomeManager process: #(0 0) and: #(1 1) ].
+	self assert: (chromosomeManager population select: [ :i | i = #(0 0) ]) size < 15.
+	self assert: (chromosomeManager population select: [ :i | i = #(1 1) ]) size < 15.
+	self assert: (chromosomeManager population select: [ :i | i = #(0 1) ]) size > 0.
+	self assert: (chromosomeManager population select: [ :i | i = #(1 0) ]) size > 0.
+	self assert: chromosomeManager population size equals: 120
 ]
 
 { #category : #tests }
@@ -149,81 +223,27 @@ PMAnotherChromosomeManagerTest >> testRandomizePopulation [
 
 	| g |
 	self setHammersleyTest: true.
-	g := cm population first.
+	g := chromosomeManager population first.
 	self setHammersleyTest: false.
-	self deny: cm population first equals: g.
-	g := cm population first.
+	self deny: chromosomeManager population first equals: g.
+	g := chromosomeManager population first.
 	self setHammersleyTest: false.
-	self deny: cm population first equals: g
+	self deny: chromosomeManager population first equals: g
 ]
 
 { #category : #tests }
 PMAnotherChromosomeManagerTest >> testRateSetting [
-self should: [cm rateOfLC: 1.3] raise:  DomainError .
-self should: [cm rateOfEir: -0.3] raise:  DomainError .
-self should: [cm rateOfMutation:  1.0000003] raise:  DomainError .
-self should: [cm rateOfCrossover:  -0.0000003] raise:  DomainError .
-self shouldnt: [cm rateOfLC: 0] raise:  Error .
-self should: [cm rateOfLC: 0.33] raise:  Warning  .
-cm rateOfLC: 0.2.
-self shouldnt: [cm rateOfEir: 0.25] raise:  Error  .
-self should: [cm rateOfEir: 0.26] raise:  Warning    .
-self should: [cm rateOfMutation: 1] raise:  Warning .
+self should: [chromosomeManager rateOfLC: 1.3] raise:  DomainError .
+self should: [chromosomeManager rateOfEir: -0.3] raise:  DomainError .
+self should: [chromosomeManager rateOfMutation:  1.0000003] raise:  DomainError .
+self should: [chromosomeManager rateOfCrossover:  -0.0000003] raise:  DomainError .
+self shouldnt: [chromosomeManager rateOfLC: 0] raise:  Error .
+self should: [chromosomeManager rateOfLC: 0.33] raise:  Warning  .
+chromosomeManager rateOfLC: 0.2.
+self shouldnt: [chromosomeManager rateOfEir: 0.25] raise:  Error  .
+self should: [chromosomeManager rateOfEir: 0.26] raise:  Warning    .
+self should: [chromosomeManager rateOfMutation: 1] raise:  Warning .
 "usual floating point inaccuracies should be accepted:"
-self shouldnt: [cm rateOfCrossover:  0.15000000000000001 ] raise:  Warning .
-self should: [cm rateOfCrossover:  0.1500001] raise:  Warning
-]
-
-{ #category : #tests }
-PMAnotherChromosomeManagerTest >> testlineCrossOver [
-	| a |
-	1 to: 10 do: [ :i |
-		a := cm lineCrossOver: #(-2 2) and: #(-4 4).
-		self assert: ((a at: 1) at: 2) equals: ((a at: 1) at: 1) negated.
-		self assert: ((a at: 2) at: 2) equals: ((a at: 2) at: 1) negated ]
-]
-
-{ #category : #tests }
-PMAnotherChromosomeManagerTest >> testnumberOfHamersleyPoints [
-	| rand |
-	self
-		assert:
-			(PMAnotherChromosomeManager
-				numberOfHamersleyPoints: 9
-				dimension: 1
-				randomized: false)
-		equals: ((1 to: 9) collect: [ :i | Array with: i * (1 / 9) ]).
-	self
-		assert:
-			(PMAnotherChromosomeManager
-				numberOfHamersleyPoints: 9
-				dimension: 4
-				randomized: false)
-		equals:
-			(OrderedCollection new
-				add: (Array  with: (1 / 9) with: (1 / 2) with: (1 / 3) with: (1 / 5));
-				add: (Array  with: (2 / 9) with: (1 / 4) with: (2 / 3) with: (2 / 5));
-				add: (Array  with: (1 / 3) with: (3 / 4) with: (1 / 9) with: (3 / 5));
-				add: (Array  with: (4 / 9) with: (1 / 8) with: (4 / 9) with: (4 / 5));
-				add: (Array  with: (5 / 9) with: (5 / 8) with: (7 / 9) with: (1 / 25));
-				add: (Array  with: (2 / 3) with: (3 / 8) with: (2 / 9) with: (6 / 25));
-				add: (Array  with: (7 / 9) with: (7 / 8) with: (5 / 9) with: (11 / 25));
-				add: (Array  with: (8 / 9) with: (1 / 16) with: (8 / 9) with: (16 / 25));
-				add: (Array  with: 1 with: (9 / 16) with: (1 / 27) with: (21 / 25));
-				asArray).
-	rand := (PMAnotherChromosomeManager
-		numberOfHamersleyPoints: 3
-		dimension: 4
-		randomized: false)
-		-
-			(PMAnotherChromosomeManager
-				numberOfHamersleyPoints: 3
-				dimension: 4
-				randomized: true).
-	rand
-		do: [ :i |
-			self assert: i first >= 0.
-			self assert: (i at: 2) < 0.
-			self assert: (i at: 3) < 0 ].
-	rand do: [ :i | i do: [ :j | j < (1 / 3) ] ]
+self shouldnt: [chromosomeManager rateOfCrossover:  0.15000000000000001 ] raise:  Warning .
+self should: [chromosomeManager rateOfCrossover:  0.1500001] raise:  Warning
 ]
diff --git a/src/Math-Tests-FunctionFit/PMAnotherGeneticOptimizerTest.class.st b/src/Math-Tests-FunctionFit/PMAnotherGeneticOptimizerTest.class.st
index 94635e186..766a39760 100644
--- a/src/Math-Tests-FunctionFit/PMAnotherGeneticOptimizerTest.class.st
+++ b/src/Math-Tests-FunctionFit/PMAnotherGeneticOptimizerTest.class.st
@@ -2,7 +2,7 @@ Class {
 	#name : #PMAnotherGeneticOptimizerTest,
 	#superclass : #TestCase,
 	#instVars : [
-		'go'
+		'geneticOptimizer'
 	],
 	#category : #'Math-Tests-FunctionFit'
 }
@@ -17,49 +17,50 @@ PMAnotherGeneticOptimizerTest >> setUp [
 	     v := x asPMVector.
 	     v * v ].
 	origin := #( -5 -5 -5 ).
-	go := PMAnotherGeneticOptimizer function: f minimumValues: origin maximumValues: origin negated.
-	go maximumIterations: 50.
-	go chromosomeManager populationSize: 20
+	geneticOptimizer := PMAnotherGeneticOptimizer function: f minimumValues: origin maximumValues: origin negated.
+	geneticOptimizer maximumIterations: 50.
+	geneticOptimizer chromosomeManager populationSize: 20.
+	geneticOptimizer chromosomeManager randomGenerator: (Random seed: 42)
 ]
 
 { #category : #tests }
 PMAnotherGeneticOptimizerTest >> testChromosomeManager [
 	self
-		assert: go chromosomeManager class
+		assert: geneticOptimizer chromosomeManager class
 		equals: PMAnotherChromosomeManager.
-	self assert: go chromosomeManager populationSize equals: 20
+	self assert: geneticOptimizer chromosomeManager populationSize equals: 20
 ]
 
 { #category : #tests }
 PMAnotherGeneticOptimizerTest >> testComputePrecision [
 |r|
-go maximumIterations: 2.
-go evaluate .
-r:=go computePrecision:0.
-go maximumIterations: 50 .
-go evaluate .
-self assert: (r>go computePrecision  )
+geneticOptimizer maximumIterations: 2.
+geneticOptimizer evaluate .
+r:=geneticOptimizer computePrecision:0.
+geneticOptimizer maximumIterations: 50 .
+geneticOptimizer evaluate .
+self assert: (r>geneticOptimizer computePrecision  )
 ]
 
 { #category : #tests }
 PMAnotherGeneticOptimizerTest >> testEvaluate [
 
-	go maximumIterations: 170.
-	go chromosomeManager populationSize: 50.
-	self assert: (go evaluate closeTo: #( 0 0 0 ))
+	geneticOptimizer maximumIterations: 170.
+	geneticOptimizer chromosomeManager populationSize: 50.
+	self assert: (geneticOptimizer evaluate closeTo: #( 0 0 0 ))
 ]
 
 { #category : #tests }
 PMAnotherGeneticOptimizerTest >> testInitializeIterations [
 
-	self assertEmpty: go bestPoints.
-	go initializeIterations.
-	self denyEmpty: go bestPoints.
-	go calcStatistics: true.
-	go evaluate.
-	self denyEmpty: go bestValueHistory.
-	go initializeIterations.
-	self assertEmpty: go bestValueHistory
+	self assertEmpty: geneticOptimizer bestPoints.
+	geneticOptimizer initializeIterations.
+	self denyEmpty: geneticOptimizer bestPoints.
+	geneticOptimizer calcStatistics: true.
+	geneticOptimizer evaluate.
+	self denyEmpty: geneticOptimizer bestValueHistory.
+	geneticOptimizer initializeIterations.
+	self assertEmpty: geneticOptimizer bestValueHistory
 ]
 
 { #category : #tests }
@@ -67,7 +68,7 @@ PMAnotherGeneticOptimizerTest >> testPrint [
 
 	| aStream s |
 	aStream := ReadWriteStream with: ''.
-	go printOn: aStream.
+	geneticOptimizer printOn: aStream.
 	s := aStream contents.
 	self assert: (s includesSubstring: 'v * v').
 	self assert: (s includesSubstring: '50').
@@ -77,12 +78,12 @@ PMAnotherGeneticOptimizerTest >> testPrint [
 { #category : #tests }
 PMAnotherGeneticOptimizerTest >> testRangeScale [
 
-	go initializeIterations.
-	self assert: (go rangeScale first closeTo: 0.1).
-	self assert: (go rangeScale second closeTo: 0.19473684210526315).
-	go initializeIterations.
-	self assert: (go rangeScale first closeTo: 0.1).
-	self assert: (go rangeScale second closeTo: 0.19473684210526315)
+	geneticOptimizer initializeIterations.
+	self assert: (geneticOptimizer rangeScale first closeTo: 0.1).
+	self assert: (geneticOptimizer rangeScale second closeTo: 0.19473684210526315).
+	geneticOptimizer initializeIterations.
+	self assert: (geneticOptimizer rangeScale first closeTo: 0.1).
+	self assert: (geneticOptimizer rangeScale second closeTo: 0.19473684210526315)
 ]
 
 { #category : #tests }
@@ -92,13 +93,13 @@ PMAnotherGeneticOptimizerTest >> testRangeScaleProbabilistic [
 	9
 		timesRepeat: [
 			self setUp.
-			go maximumIterations: 500.
-			go rangeScale: true.
-			r1 := go evaluate norm.
+			geneticOptimizer maximumIterations: 500.
+			geneticOptimizer rangeScale: true.
+			r1 := geneticOptimizer evaluate norm.
 			self setUp.
-			go maximumIterations: 500.
-			go rangeScale: false.
-			r2 := go evaluate norm.
+			geneticOptimizer maximumIterations: 500.
+			geneticOptimizer rangeScale: false.
+			r2 := geneticOptimizer evaluate norm.
 			correct := r1 < r2
 				ifTrue: [ correct + 1 ]
 				ifFalse: [ correct - 1 ] ].
@@ -112,13 +113,13 @@ PMAnotherGeneticOptimizerTest >> testRemoveLastProbabilistic [
 	3
 		timesRepeat: [
 			self setUp.
-			go maximumIterations: 1000.
-			go removeLast: true.
-			r1 := go evaluate norm.
+			geneticOptimizer maximumIterations: 1000.
+			geneticOptimizer removeLast: true.
+			r1 := geneticOptimizer evaluate norm.
 			self setUp.
-			go maximumIterations: 1000.
-			go removeLast: false.
-			r2 := go evaluate norm.
+			geneticOptimizer maximumIterations: 1000.
+			geneticOptimizer removeLast: false.
+			r2 := geneticOptimizer evaluate norm.
 			correct := r1 > r2
 				ifTrue: [ correct + 1 ]
 				ifFalse: [ correct - 1 ] ].
@@ -129,39 +130,39 @@ PMAnotherGeneticOptimizerTest >> testRemoveLastProbabilistic [
 PMAnotherGeneticOptimizerTest >> testSteadyState [
 |r1 r2|
 "probabilistic test. not always true"
-go steadyState:  false.
-go maximumIterations: 1000.
-r1 :=go evaluate norm.
+geneticOptimizer steadyState:  false.
+geneticOptimizer maximumIterations: 1000.
+r1 :=geneticOptimizer evaluate norm.
 self setUp .
-go steadyState:  true.
-go maximumIterations: 1000.
-r2 :=go evaluate norm.
+geneticOptimizer steadyState:  true.
+geneticOptimizer maximumIterations: 1000.
+r2 :=geneticOptimizer evaluate norm.
 self assert: (r1>r2  )
 ]
 
 { #category : #tests }
 PMAnotherGeneticOptimizerTest >> testaddPointAt [
 	| b |
-	go chromosomeManager populationSize: 2.
-	go resetBestPoints.
-	go addPointAt: #(0 1 0).
-	b := go bestPoints.
+	geneticOptimizer chromosomeManager populationSize: 2.
+	geneticOptimizer resetBestPoints.
+	geneticOptimizer addPointAt: #(0 1 0).
+	b := geneticOptimizer bestPoints.
 	self assert: b first position equals: #(0 1 0).
 	self assert: b first value equals: 1.
-	go addPointAt: (Array with: 0 with: Float nan with: 0).
-	self assert: go bestPoints equals: b.
-	go addPointAt: (Array with: (0 - Float infinity) with: 0 with: 0).
-	self assert: go bestPoints equals: b.
-	go addPointAt: #(1 1 0).
-	b := go bestPoints.
+	geneticOptimizer addPointAt: (Array with: 0 with: Float nan with: 0).
+	self assert: geneticOptimizer bestPoints equals: b.
+	geneticOptimizer addPointAt: (Array with: (0 - Float infinity) with: 0 with: 0).
+	self assert: geneticOptimizer bestPoints equals: b.
+	geneticOptimizer addPointAt: #(1 1 0).
+	b := geneticOptimizer bestPoints.
 	self assert: b size equals: 2.
-	go addPointAt: #(2 1 0).
-	self assert: go bestPoints equals: b.
-	go addPointAt: #(0 0.9 0).
+	geneticOptimizer addPointAt: #(2 1 0).
+	self assert: geneticOptimizer bestPoints equals: b.
+	geneticOptimizer addPointAt: #(0 0.9 0).
 	self assert: b first position equals: #(0 0.9 0).
 	self assert: b second position equals: #(0 1 0).	"never throw away old first position"
-	go removeLast: true.
-	go addPointAt: #(0 0.89 0).
+	geneticOptimizer removeLast: true.
+	geneticOptimizer addPointAt: #(0 0.89 0).
 	self assert: b first position equals: #(0 0.89 0).
 	self assert: b second position equals: #(0 0.9 0)
 ]
@@ -170,22 +171,22 @@ PMAnotherGeneticOptimizerTest >> testaddPointAt [
 PMAnotherGeneticOptimizerTest >> testcalcStatistics [
 
 	| s |
-	go evaluate.
-	self assertEmpty: go bestValueHistory.
-	self assertEmpty: go worstValueHistory.
-	self assertEmpty: go whateverHistory.
-	go calcStatistics: true.
-	go evaluate.
-	s := go iterations.
-	self assert: go bestValueHistory size equals: s.
-	self assert: go worstValueHistory size equals: s.
-	self assert: go whateverHistory size equals: s
+	geneticOptimizer evaluate.
+	self assertEmpty: geneticOptimizer bestValueHistory.
+	self assertEmpty: geneticOptimizer worstValueHistory.
+	self assertEmpty: geneticOptimizer whateverHistory.
+	geneticOptimizer calcStatistics: true.
+	geneticOptimizer evaluate.
+	s := geneticOptimizer iterations.
+	self assert: geneticOptimizer bestValueHistory size equals: s.
+	self assert: geneticOptimizer worstValueHistory size equals: s.
+	self assert: geneticOptimizer whateverHistory size equals: s
 ]
 
 { #category : #tests }
 PMAnotherGeneticOptimizerTest >> testresetBestPoints [
 
-	go evaluate.
-	go resetBestPoints.
-	self assertEmpty: go bestPoints
+	geneticOptimizer evaluate.
+	geneticOptimizer resetBestPoints.
+	self assertEmpty: geneticOptimizer bestPoints
 ]
diff --git a/src/Math-Tests-FunctionFit/PMGeneralFunctionFitTest.class.st b/src/Math-Tests-FunctionFit/PMGeneralFunctionFitTest.class.st
index d058e1c39..69ce3c41d 100644
--- a/src/Math-Tests-FunctionFit/PMGeneralFunctionFitTest.class.st
+++ b/src/Math-Tests-FunctionFit/PMGeneralFunctionFitTest.class.st
@@ -31,10 +31,9 @@ PMGeneralFunctionFitTest >> testBasic [
 		       data: col
 		       minimumValues: 0
 		       maximumValues: 5.
+	fit manager randomGenerator: (Random seed: 42).
 	self assert: (fit evaluate closeTo: #( 0.1 0.4 )).
-	(fit result - #( 0.1 0.4 )) abs
-		with: (fit secondaryResult - #( 0.1 0.4 )) abs
-		do: [ :e :s | self assert: s - e > 0 ].
+	(fit result - #( 0.1 0.4 )) abs with: (fit secondaryResult - #( 0.1 0.4 )) abs do: [ :e :s | self assert: s - e > 0 ].
 	d := fit error: fit secondaryResult.
 	self assert: d < 1e-5.
 	self assert: fit error < d
@@ -49,6 +48,7 @@ PMGeneralFunctionFitTest >> testFunction [
 		       data: col
 		       minimumValues: 0
 		       maximumValues: 5.
+	fit manager randomGenerator: (Random seed: 42).
 	y := fit function value: 3 value: 0.1 value: 0.4.
 	fit evaluate.
 	self assert: ((fit function value: 3) closeTo: y)
@@ -67,25 +67,26 @@ PMGeneralFunctionFitTest >> testManager [
 
 { #category : #tests }
 PMGeneralFunctionFitTest >> testMaximumIterationsProbabilistic [
+
 	| r correct |
 	fit := PMGeneralFunctionFit
-		function: f
-		data: col
-		minimumValues: 0
-		maximumValues: 5.
+		       function: f
+		       data: col
+		       minimumValues: 0
+		       maximumValues: 5.
 	correct := 0.
 	fit populationSize: 20.
-	7
-		timesRepeat: [
-			fit resetBestPoints.
-			fit maximumIterations: 200.
-			r := (fit evaluate - #(0.1 0.4)) abs.
-			fit resetBestPoints.
-			fit maximumIterations: 2.
-			r := (fit evaluate - #(0.1 0.4)) abs - r.
-			correct := ((r at: 1) > 0 or: [ (r at: 2) > 0 ])
-				ifTrue: [ correct + 1 ]
-				ifFalse: [ correct - 1 ] ].
+	fit manager randomGenerator: (Random seed: 42).
+	7 timesRepeat: [
+		fit resetBestPoints.
+		fit maximumIterations: 200.
+		r := (fit evaluate - #( 0.1 0.4 )) abs.
+		fit resetBestPoints.
+		fit maximumIterations: 2.
+		r := (fit evaluate - #( 0.1 0.4 )) abs - r.
+		correct := ((r at: 1) > 0 or: [ (r at: 2) > 0 ])
+			           ifTrue: [ correct + 1 ]
+			           ifFalse: [ correct - 1 ] ].
 	self assert: correct > 0
 ]
 
@@ -103,28 +104,41 @@ PMGeneralFunctionFitTest >> testPopulationSize [
 
 { #category : #tests }
 PMGeneralFunctionFitTest >> testPrecision [
-fit:=PMGeneralFunctionFit function: f data: col minimumValues: 0 maximumValues: 5 .
-self assert:fit precision isNil.
-fit evaluate .
-self assert: (fit precision < 1e-6 )
+
+	fit := PMGeneralFunctionFit
+		       function: f
+		       data: col
+		       minimumValues: 0
+		       maximumValues: 5.
+	fit manager randomGenerator: (Random seed: 42).
+	self assert: fit precision isNil.
+	fit evaluate.
+	self assert: fit precision < 1e-6
 ]
 
 { #category : #tests }
 PMGeneralFunctionFitTest >> testPrint [
-|aStream s|
-fit:=PMGeneralFunctionFit function: f data: col minimumValues: 0 maximumValues: 5 .
-aStream :=ReadWriteStream with:''.
-fit printOn: aStream .
-s :=aStream contents .
-self assert: (s includesSubstring: '(a * x) sin / (b + x squared)').
-self assert: (s includesSubstring: '#squared').
-self assert: (s includesSubstring: '81').
-self deny: (s includesSubstring: '#(0.').
-fit evaluate .
-aStream :=ReadWriteStream with:''.
-fit printOn: aStream .
-s :=aStream contents .
-self assert: (s includesSubstring: '#(0.')
+
+	| aStream s |
+	fit := PMGeneralFunctionFit
+		       function: f
+		       data: col
+		       minimumValues: 0
+		       maximumValues: 5.
+
+	fit manager randomGenerator: (Random seed: 42).
+	aStream := ReadWriteStream with: ''.
+	fit printOn: aStream.
+	s := aStream contents.
+	self assert: (s includesSubstring: '(a * x) sin / (b + x squared)').
+	self assert: (s includesSubstring: '#squared').
+	self assert: (s includesSubstring: '81').
+	self deny: (s includesSubstring: '#(0.').
+	fit evaluate.
+	aStream := ReadWriteStream with: ''.
+	fit printOn: aStream.
+	s := aStream contents.
+	self assert: (s includesSubstring: '#(0.')
 ]
 
 { #category : #tests }
@@ -138,6 +152,8 @@ PMGeneralFunctionFitTest >> testRelativeError [
 		       data: col
 		       minimumValues: -6
 		       maximumValues: 6.
+
+	fit manager randomGenerator: (Random seed: 42).
 	fit populationSize: 10.
 	r := fit evaluate first.
 	self assert: (r closeTo: 4).
@@ -159,6 +175,8 @@ PMGeneralFunctionFitTest >> testResetBestPoints [
 		       data: col
 		       minimumValues: 0
 		       maximumValues: 5.
+
+	fit manager randomGenerator: (Random seed: 42).
 	fit evaluate.
 	fit resetBestPoints.
 	self assertEmpty: fit optimizer bestPoints
@@ -175,6 +193,8 @@ PMGeneralFunctionFitTest >> testTruncate [
 		       data: col
 		       minimumValues: 0
 		       maximumValues: 5.
+
+	fit manager randomGenerator: (Random seed: 42).
 	fit errorType: #quartile.
 	self assert: (fit findQuartile closeTo: #( 0.1 0.4 )).
 	self assert: fit quartile < (79 / 81).
@@ -182,9 +202,7 @@ PMGeneralFunctionFitTest >> testTruncate [
 	self deny: fit dataTruncated.
 	fit truncateData.
 	self assert: fit dataTruncated.
-	self
-		assert: fit optimizer functionBlock data size
-		equals: fit quartile * col size.
+	self assert: fit optimizer functionBlock data size equals: fit quartile * col size.
 	fit errorType: #abs.
 	self assert: fit errorType equals: #abs.
 	self assert: (fit evaluate closeTo: #( 0.1 0.4 )).

From 8f7faf6c0d97a8cf31d1ee77597ee8be6f06bd33 Mon Sep 17 00:00:00 2001
From: CyrilFerlicot <cyril@ferlicot.me>
Date: Mon, 13 Mar 2023 16:21:38 +0100
Subject: [PATCH 3/4] Factorize code

---
 .../PMGeneralFunctionFitTest.class.st         | 65 ++++---------------
 1 file changed, 13 insertions(+), 52 deletions(-)

diff --git a/src/Math-Tests-FunctionFit/PMGeneralFunctionFitTest.class.st b/src/Math-Tests-FunctionFit/PMGeneralFunctionFitTest.class.st
index 69ce3c41d..889dea20a 100644
--- a/src/Math-Tests-FunctionFit/PMGeneralFunctionFitTest.class.st
+++ b/src/Math-Tests-FunctionFit/PMGeneralFunctionFitTest.class.st
@@ -19,19 +19,20 @@ PMGeneralFunctionFitTest >> setUp [
 	"Reset the FloatingPointMachine to make coverage consistent"
 	PMFloatingPointMachine reset.
 	f := [ :x :a :b | (a * x) sin / (b + x squared) ].
-	col := (-4 to: 4 by: 0.1) collect: [ :i | i @ (f cull: i cull: 0.1 cull: 0.4) ]
+	col := (-4 to: 4 by: 0.1) collect: [ :i | i @ (f cull: i cull: 0.1 cull: 0.4) ].
+	fit := PMGeneralFunctionFit
+		       function: f
+		       data: col
+		       minimumValues: 0
+		       maximumValues: 5.
+
+	fit manager randomGenerator: (Random seed: 42)
 ]
 
 { #category : #tests }
 PMGeneralFunctionFitTest >> testBasic [
 
 	| d |
-	fit := PMGeneralFunctionFit
-		       function: f
-		       data: col
-		       minimumValues: 0
-		       maximumValues: 5.
-	fit manager randomGenerator: (Random seed: 42).
 	self assert: (fit evaluate closeTo: #( 0.1 0.4 )).
 	(fit result - #( 0.1 0.4 )) abs with: (fit secondaryResult - #( 0.1 0.4 )) abs do: [ :e :s | self assert: s - e > 0 ].
 	d := fit error: fit secondaryResult.
@@ -43,12 +44,6 @@ PMGeneralFunctionFitTest >> testBasic [
 PMGeneralFunctionFitTest >> testFunction [
 
 	| y |
-	fit := PMGeneralFunctionFit
-		       function: f
-		       data: col
-		       minimumValues: 0
-		       maximumValues: 5.
-	fit manager randomGenerator: (Random seed: 42).
 	y := fit function value: 3 value: 0.1 value: 0.4.
 	fit evaluate.
 	self assert: ((fit function value: 3) closeTo: y)
@@ -56,27 +51,17 @@ PMGeneralFunctionFitTest >> testFunction [
 
 { #category : #tests }
 PMGeneralFunctionFitTest >> testManager [
-	fit := PMGeneralFunctionFit
-		function: f
-		data: col
-		minimumValues: 0
-		maximumValues: 5.
+
 	self assert: fit manager class equals: PMAnotherChromosomeManager.
-	self assert: fit manager range equals: #(5 5)
+	self assert: fit manager range equals: #( 5 5 )
 ]
 
 { #category : #tests }
 PMGeneralFunctionFitTest >> testMaximumIterationsProbabilistic [
 
 	| r correct |
-	fit := PMGeneralFunctionFit
-		       function: f
-		       data: col
-		       minimumValues: 0
-		       maximumValues: 5.
 	correct := 0.
 	fit populationSize: 20.
-	fit manager randomGenerator: (Random seed: 42).
 	7 timesRepeat: [
 		fit resetBestPoints.
 		fit maximumIterations: 200.
@@ -92,11 +77,7 @@ PMGeneralFunctionFitTest >> testMaximumIterationsProbabilistic [
 
 { #category : #tests }
 PMGeneralFunctionFitTest >> testPopulationSize [
-	fit := PMGeneralFunctionFit
-		function: f
-		data: col
-		minimumValues: 0
-		maximumValues: 5.
+
 	self assert: fit manager populationSize equals: 50.
 	fit populationSize: 100.
 	self assert: fit manager populationSize equals: 100
@@ -105,12 +86,6 @@ PMGeneralFunctionFitTest >> testPopulationSize [
 { #category : #tests }
 PMGeneralFunctionFitTest >> testPrecision [
 
-	fit := PMGeneralFunctionFit
-		       function: f
-		       data: col
-		       minimumValues: 0
-		       maximumValues: 5.
-	fit manager randomGenerator: (Random seed: 42).
 	self assert: fit precision isNil.
 	fit evaluate.
 	self assert: fit precision < 1e-6
@@ -120,13 +95,6 @@ PMGeneralFunctionFitTest >> testPrecision [
 PMGeneralFunctionFitTest >> testPrint [
 
 	| aStream s |
-	fit := PMGeneralFunctionFit
-		       function: f
-		       data: col
-		       minimumValues: 0
-		       maximumValues: 5.
-
-	fit manager randomGenerator: (Random seed: 42).
 	aStream := ReadWriteStream with: ''.
 	fit printOn: aStream.
 	s := aStream contents.
@@ -150,8 +118,8 @@ PMGeneralFunctionFitTest >> testRelativeError [
 	fit := PMGeneralFunctionFit
 		       function: f
 		       data: col
-		       minimumValues: -6
-		       maximumValues: 6.
+		       minimumValues: 0
+		       maximumValues: 5.
 
 	fit manager randomGenerator: (Random seed: 42).
 	fit populationSize: 10.
@@ -170,13 +138,6 @@ PMGeneralFunctionFitTest >> testRelativeError [
 { #category : #tests }
 PMGeneralFunctionFitTest >> testResetBestPoints [
 
-	fit := PMGeneralFunctionFit
-		       function: f
-		       data: col
-		       minimumValues: 0
-		       maximumValues: 5.
-
-	fit manager randomGenerator: (Random seed: 42).
 	fit evaluate.
 	fit resetBestPoints.
 	self assertEmpty: fit optimizer bestPoints

From a697e1473de3ad6d2042adb1b66c0b11126b1154 Mon Sep 17 00:00:00 2001
From: CyrilFerlicot <cyril@ferlicot.me>
Date: Mon, 13 Mar 2023 16:27:27 +0100
Subject: [PATCH 4/4] Revert a change that was not suppose to happen

---
 src/Math-Tests-FunctionFit/PMGeneralFunctionFitTest.class.st | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/Math-Tests-FunctionFit/PMGeneralFunctionFitTest.class.st b/src/Math-Tests-FunctionFit/PMGeneralFunctionFitTest.class.st
index 889dea20a..b87af1fea 100644
--- a/src/Math-Tests-FunctionFit/PMGeneralFunctionFitTest.class.st
+++ b/src/Math-Tests-FunctionFit/PMGeneralFunctionFitTest.class.st
@@ -118,8 +118,8 @@ PMGeneralFunctionFitTest >> testRelativeError [
 	fit := PMGeneralFunctionFit
 		       function: f
 		       data: col
-		       minimumValues: 0
-		       maximumValues: 5.
+		       minimumValues: -6
+		       maximumValues: 6.
 
 	fit manager randomGenerator: (Random seed: 42).
 	fit populationSize: 10.