68 lines
1.5 KiB
Go
68 lines
1.5 KiB
Go
package sequence
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import (
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"math"
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"math/rand"
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"time"
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)
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// RandomValues returns an array of random values.
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func RandomValues(count int) []float64 {
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return Seq{NewRandom().WithLen(count)}.Array()
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}
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// RandomValuesWithAverage returns an array of random values with a given average.
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func RandomValuesWithAverage(average float64, count int) []float64 {
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return Seq{NewRandom().WithAverage(average).WithLen(count)}.Array()
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}
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// NewRandom creates a new random sequence.
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func NewRandom() *Random {
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return &Random{
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rnd: rand.New(rand.NewSource(time.Now().Unix())),
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}
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}
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// Random is a random number sequence generator.
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type Random struct {
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rnd *rand.Rand
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scale *float64
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average *float64
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len *int
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}
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// Len returns the number of elements that will be generated.
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func (r *Random) Len() int {
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if r.len != nil {
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return *r.len
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}
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return math.MaxInt32
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}
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// GetValue returns the value.
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func (r *Random) GetValue(_ int) float64 {
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if r.average != nil && r.scale != nil {
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return *r.average + *r.scale - (r.rnd.Float64() * (2 * *r.scale))
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} else if r.scale != nil {
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return r.rnd.Float64() * *r.scale
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}
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return r.rnd.Float64()
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}
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// WithLen sets a maximum len
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func (r *Random) WithLen(length int) *Random {
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r.len = &length
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return r
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}
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// WithScale sets the scale and returns the Random.
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func (r *Random) WithScale(scale float64) *Random {
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r.scale = &scale
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return r
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}
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// WithAverage sets the average and returns the Random.
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func (r *Random) WithAverage(average float64) *Random {
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r.average = &average
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return r
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}
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