mirror of
https://source.quilibrium.com/quilibrium/ceremonyclient.git
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55 lines
1.5 KiB
Go
55 lines
1.5 KiB
Go
// Copyright 2018 The Cockroach Authors.
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//
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// Licensed under the Apache License, Version 2.0 (the "License");
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// you may not use this file except in compliance with the License.
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// You may obtain a copy of the License at
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//
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// http://www.apache.org/licenses/LICENSE-2.0
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//
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// Unless required by applicable law or agreed to in writing, software
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// distributed under the License is distributed on an "AS IS" BASIS,
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// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
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// implied. See the License for the specific language governing
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// permissions and limitations under the License. See the AUTHORS file
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// for names of contributors.
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package randvar
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import (
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"sync/atomic"
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"golang.org/x/exp/rand"
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)
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// Uniform is a random number generator that generates draws from a uniform
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// distribution.
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type Uniform struct {
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min uint64
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max atomic.Uint64
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}
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// NewUniform constructs a new Uniform generator with the given
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// parameters. Returns an error if the parameters are outside the accepted
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// range.
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func NewUniform(min, max uint64) *Uniform {
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u := &Uniform{min: min}
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u.max.Store(max)
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return u
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}
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// IncMax increments max.
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func (g *Uniform) IncMax(delta int) {
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g.max.Add(uint64(delta))
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}
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// Max returns the max value of the distribution.
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func (g *Uniform) Max() uint64 {
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return g.max.Load()
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}
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// Uint64 returns a random Uint64 between min and max, drawn from a uniform
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// distribution.
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func (g *Uniform) Uint64(rng *rand.Rand) uint64 {
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return rng.Uint64n(g.Max()-g.min+1) + g.min
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}
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