92 lines
2.7 KiB
C#
92 lines
2.7 KiB
C#
/*
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* Copyright 2018 The Cartographer 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 implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*/
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namespace CartographerSharp.Metrics;
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/// <summary>
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/// Histogram metric for tracking value distributions.
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/// </summary>
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public abstract class Histogram
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{
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/// <summary>
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/// Bucket boundaries for histogram.
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/// </summary>
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public class BucketBoundaries : List<double>
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{
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public BucketBoundaries() : base() { }
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public BucketBoundaries(IEnumerable<double> collection) : base(collection) { }
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}
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/// <summary>
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/// Histogram instance that does nothing. Safe for use in static initializers.
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/// </summary>
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public static Histogram Null()
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{
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return new NullHistogram();
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}
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/// <summary>
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/// Creates fixed-width bucket boundaries.
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/// </summary>
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public static BucketBoundaries FixedWidth(double width, int numFiniteBuckets)
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{
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var result = new BucketBoundaries();
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double boundary = 0;
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for (int i = 0; i < numFiniteBuckets; i++)
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{
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boundary += width;
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result.Add(boundary);
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}
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return result;
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}
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/// <summary>
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/// Creates scaled powers-of bucket boundaries.
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/// </summary>
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public static BucketBoundaries ScaledPowersOf(double baseValue, double scaleFactor, double maxValue)
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{
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if (baseValue <= 1)
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throw new ArgumentException("Base must be greater than 1", nameof(baseValue));
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if (scaleFactor <= 0)
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throw new ArgumentException("Scale factor must be greater than 0", nameof(scaleFactor));
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var result = new BucketBoundaries();
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double boundary = scaleFactor;
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while (boundary < maxValue)
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{
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result.Add(boundary);
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boundary *= baseValue;
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}
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return result;
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}
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/// <summary>
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/// Observes a value in the histogram.
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/// </summary>
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public abstract void Observe(double value);
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}
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/// <summary>
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/// Null implementation of histogram that does nothing.
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/// </summary>
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internal class NullHistogram : Histogram
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{
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public override void Observe(double value)
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{
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// Do nothing
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}
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}
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