fixing examples

seq/random.go

@@ -12,8 +12,8 @@ func RandomValues(count int) []float64 {
 }
 
 // RandomValuesWithAverage returns an array of random values with a given average.
-func RandomValuesWithAverage(average float64, count int) []float64 {
-	return Seq{NewRandom().WithAverage(average).WithLen(count)}.Array()
+func RandomValuesWithMax(count int, max float64) []float64 {
+	return Seq{NewRandom().WithMax(max).WithLen(count)}.Array()
 }
 
 // NewRandom creates a new random seq.
@@ -25,10 +25,10 @@ func NewRandom() *Random {
 
 // Random is a random number seq generator.
 type Random struct {
-	rnd     *rand.Rand
-	scale   *float64
-	average *float64
-	len     *int
+	rnd *rand.Rand
+	max *float64
+	min *float64
+	len *int
 }
 
 // Len returns the number of elements that will be generated.
@@ -41,10 +41,20 @@ func (r *Random) Len() int {
 
 // GetValue returns the value.
 func (r *Random) GetValue(_ int) float64 {
-	if r.average != nil && r.scale != nil {
-		return *r.average + *r.scale - (r.rnd.Float64() * (2 * *r.scale))
-	} else if r.scale != nil {
-		return r.rnd.Float64() * *r.scale
+	if r.min != nil && r.max != nil {
+		var delta float64
+
+		if *r.max > *r.min {
+			delta = *r.max - *r.min
+		} else {
+			delta = *r.min - *r.max
+		}
+
+		return *r.min + (r.rnd.Float64() * delta)
+	} else if r.max != nil {
+		return r.rnd.Float64() * *r.max
+	} else if r.min != nil {
+		return *r.min + (r.rnd.Float64())
 	}
 	return r.rnd.Float64()
 }
@@ -55,24 +65,24 @@ func (r *Random) WithLen(length int) *Random {
 	return r
 }
 
-// Scale returns the scale.
-func (r Random) Scale() *float64 {
-	return r.scale
+// Min returns the minimum value.
+func (r Random) Min() *float64 {
+	return r.min
 }
 
-// WithScale sets the scale and returns the Random.
-func (r *Random) WithScale(scale float64) *Random {
-	r.scale = &scale
+// WithMin sets the scale and returns the Random.
+func (r *Random) WithMin(min float64) *Random {
+	r.min = &min
 	return r
 }
 
-// Average returns the average.
-func (r Random) Average() *float64 {
-	return r.average
+// Max returns the maximum value.
+func (r Random) Max() *float64 {
+	return r.max
 }
 
-// WithAverage sets the average and returns the Random.
-func (r *Random) WithAverage(average float64) *Random {
-	r.average = &average
+// WithMax sets the average and returns the Random.
+func (r *Random) WithMax(max float64) *Random {
+	r.max = &max
 	return r
 }

seq/random_test.go

@@ -9,10 +9,12 @@ import (
 func TestRandomRegression(t *testing.T) {
 	assert := assert.New(t)
 
-	randomProvider := NewRandom().WithLen(100).WithAverage(256)
-	assert.Equal(100, randomProvider.Len())
-	assert.Equal(256, *randomProvider.Average())
+	randomProvider := NewRandom().WithLen(4096).WithMax(256)
+	assert.Equal(4096, randomProvider.Len())
+	assert.Equal(256, *randomProvider.Max())
 
-	randomValues := New(randomProvider).Array()
-	assert.Len(randomValues, 100)
+	randomSequence := New(randomProvider)
+	randomValues := randomSequence.Array()
+	assert.Len(randomValues, 4096)
+	assert.InDelta(128, randomSequence.Average(), 10.0)
 }