From 7db2f1b6323b6794b3a957732d88eb514d30429a Mon Sep 17 00:00:00 2001 From: zhengcheng Date: Tue, 13 Dec 2022 21:50:32 +0800 Subject: [PATCH] =?UTF-8?q?=E7=9B=B4=E6=96=B9=E5=9B=BE?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit --- src/util/histogram.rs | 356 +++++++++++++++++++++++++++++++++++++ src/util/histogram_test.rs | 13 ++ src/util/mod.rs | 4 +- 3 files changed, 372 insertions(+), 1 deletion(-) create mode 100644 src/util/histogram.rs create mode 100644 src/util/histogram_test.rs diff --git a/src/util/histogram.rs b/src/util/histogram.rs new file mode 100644 index 0000000..5a0145b --- /dev/null +++ b/src/util/histogram.rs @@ -0,0 +1,356 @@ +use std::fmt::{Display, Formatter}; +/// 直方图的桶个数 +const K_NUM_BUCKETS: usize = 154; +/// 直方图每个桶可存放值的上界，开区间 +const K_BUCKET_LIMIT: [f64; K_NUM_BUCKETS] = [ + 1.0, + 2.0, + 3.0, + 4.0, + 5.0, + 6.0, + 7.0, + 8.0, + 9.0, + 10.0, + 12.0, + 14.0, + 16.0, + 18.0, + 20.0, + 25.0, + 30.0, + 35.0, + 40.0, + 45.0, + 50.0, + 60.0, + 70.0, + 80.0, + 90.0, + 100.0, + 120.0, + 140.0, + 160.0, + 180.0, + 200.0, + 250.0, + 300.0, + 350.0, + 400.0, + 450.0, + 500.0, + 600.0, + 700.0, + 800.0, + 900.0, + 1000.0, + 1200.0, + 1400.0, + 1600.0, + 1800.0, + 2000.0, + 2500.0, + 3000.0, + 3500.0, + 4000.0, + 4500.0, + 5000.0, + 6000.0, + 7000.0, + 8000.0, + 9000.0, + 10000.0, + 12000.0, + 14000.0, + 16000.0, + 18000.0, + 20000.0, + 25000.0, + 30000.0, + 35000.0, + 40000.0, + 45000.0, + 50000.0, + 60000.0, + 70000.0, + 80000.0, + 90000.0, + 100000.0, + 120000.0, + 140000.0, + 160000.0, + 180000.0, + 200000.0, + 250000.0, + 300000.0, + 350000.0, + 400000.0, + 450000.0, + 500000.0, + 600000.0, + 700000.0, + 800000.0, + 900000.0, + 1000000.0, + 1200000.0, + 1400000.0, + 1600000.0, + 1800000.0, + 2000000.0, + 2500000.0, + 3000000.0, + 3500000.0, + 4000000.0, + 4500000.0, + 5000000.0, + 6000000.0, + 7000000.0, + 8000000.0, + 9000000.0, + 10000000.0, + 12000000.0, + 14000000.0, + 16000000.0, + 18000000.0, + 20000000.0, + 25000000.0, + 30000000.0, + 35000000.0, + 40000000.0, + 45000000.0, + 50000000.0, + 60000000.0, + 70000000.0, + 80000000.0, + 90000000.0, + 100000000.0, + 120000000.0, + 140000000.0, + 160000000.0, + 180000000.0, + 200000000.0, + 250000000.0, + 300000000.0, + 350000000.0, + 400000000.0, + 450000000.0, + 500000000.0, + 600000000.0, + 700000000.0, + 800000000.0, + 900000000.0, + 1000000000.0, + 1200000000.0, + 1400000000.0, + 1600000000.0, + 1800000000.0, + 2000000000.0, + 2500000000.0, + 3000000000.0, + 3500000000.0, + 4000000000.0, + 4500000000.0, + 5000000000.0, + 6000000000.0, + 7000000000.0, + 8000000000.0, + 9000000000.0, + 1e200_f64]; + +/// 直方图 +pub struct Histogram { + min: f64, + max: f64, + num: f64, + sum: f64, + sumSquares: f64, + buckets: [f64; K_NUM_BUCKETS] +} + +impl Default for Histogram { + fn default() -> Self { + Self { + min: K_BUCKET_LIMIT[K_NUM_BUCKETS - 1], + max: 0.0, + num: 0.0, + sum: 0.0, + sumSquares: 0.0, + buckets: [0.0; K_NUM_BUCKETS] + } + } +} + +/// 实现Display，自动提供to_string +impl Display for Histogram { + fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result { + let mut print = String::new(); + print.push_str(&format!("Count: {:.0} Average: {:.4} StdDev: {:.2} \n", + self.num, self.average(), self.standard_deviation())); + print.push_str(&format!("Min: {:.4} Median: {:.4} Max: {:.4} \n", + self.min, self.median(), self.max)); + print.push_str("------------------------------------------------------\n"); + + let mult = 100.0 / self.num; + let mut sum:f64 = 0.0; + for i in 0..K_NUM_BUCKETS { + if self.buckets[i] <= 0.0 { + continue; + } + sum += self.buckets[i]; + print.push_str(&format!("[ {:>7.0}, {:>7.0} ) {:>7.0} {:>7.3}% {:>7.3}% ", + if i == 0 {0.0} else {K_BUCKET_LIMIT[i - 1]}, // 左端点 + K_BUCKET_LIMIT[i], // 右端点 + self.buckets[i], // 计数 + mult * self.buckets[i], // 百分比 + mult * sum)); // 累计百分比 + // 基于百分比的hash marks；100%为20 mark + let mark:f64 = 20.0 * (self.buckets[i] / self.num); + print.push_str(&format!("{:.0}#\n", mark)); + } + write!(f, "{}", print) + } +} + +impl Histogram { + /// 清空直方图数据 + /// + /// # Arguments + /// + /// + /// returns: () + /// + /// # Examples + /// + /// ``` + /// let mut histogram = Histogram::default(); + /// histogram.clear(); + /// ``` + pub fn clear(&mut self) { + self.min = K_BUCKET_LIMIT[K_NUM_BUCKETS - 1]; + self.max = 0.0; + self.num = 0.0; + self.sum = 0.0; + self.sumSquares = 0.0; + for i in 0..K_NUM_BUCKETS { + self.buckets[i] = 0.0; + } + } + /// 向直方图中添加一条新值 + /// + /// # Arguments + /// + /// * `value`: 待添加的值 + /// + /// returns: () + /// + /// # Examples + /// + /// ``` + /// let mut histogram = Histogram::default(); + /// histogram.add(1.0); + /// ``` + pub fn add(&mut self, value: f64) { + let mut index = 0; + // 找到值所属的桶 + while index < K_NUM_BUCKETS - 1 && K_BUCKET_LIMIT[index] <= value { + index += 1; + } + self.buckets[index] += 1.0; + if self.min > value { + self.min = value; + } + if self.max < value { + self.max = value; + } + self.num += 1.0; + self.sum += value; + self.sumSquares += value * value; + } + /// 合并另一个直方图的数据到当前直方图 + /// + /// # Arguments + /// + /// * `other`:另一个直方图 + /// + /// returns: () + /// + /// # Examples + /// + /// ``` + /// let mut histogram = Histogram::default(); + /// let other = Histogram::default(); + /// histogram.merge(other); + /// ``` + pub fn merge(&mut self, other: &Self) { + if self.min > other.min { + self.min = other.min; + } + if self.max < other.max { + self.max = other.max; + } + self.num += other.num; + self.sum += other.sum; + self.sumSquares += other.sumSquares; + for i in 0..K_NUM_BUCKETS { + self.buckets[i] += other.buckets[i]; + } + } + + /// + /// + /// # Arguments + /// + /// * `p`: + /// + /// returns: f64 + /// + /// # Examples + /// + /// ``` + /// + /// ``` + fn percentile(&self, p :f64) -> f64 { + let threhold = self.num * ( p / 100.0); + let mut sum :f64 = 0.0; + for i in 0..K_NUM_BUCKETS { + sum += self.buckets[i]; + if sum >= threhold { + let leftPoint :f64 = if i == 0 {0.0} else {K_BUCKET_LIMIT[i - 1]}; + let rightPoint :f64 = K_BUCKET_LIMIT[i]; + let leftSum :f64 = sum - self.buckets[i]; + let rightSum :f64 = sum; + let pos :f64 = (threhold - leftSum) / (rightSum - leftSum); + let mut r :f64 = leftPoint + (rightPoint - leftPoint) * pos; + if r < self.min { + r = self.min; + } + if r > self.max { + r = self.max; + } + return r; + } + } + return self.max; + } + + fn median(&self) -> f64 { + return self.percentile(50.0); + } + + /// 求平均值 + fn average(&self) -> f64 { + if self.sum == 0.0 { + return 0.0; + } + return self.sum / self.num; + } + + fn standard_deviation(&self) -> f64 { + if self.sum == 0.0 { + return 0.0; + } + let variance = (self.sumSquares * self.num - self.sum * self.sum) / (self.num * self.num); + return variance.sqrt(); + } +} \ No newline at end of file diff --git a/src/util/histogram_test.rs b/src/util/histogram_test.rs new file mode 100644 index 0000000..50c5a58 --- /dev/null +++ b/src/util/histogram_test.rs @@ -0,0 +1,13 @@ + +mod test{ + use crate::util::histogram::Histogram; + + #[test] + fn test_add() { + let mut histogram = Histogram::default(); + histogram.add(1.0); + histogram.add(0.2); + histogram.add(6.0); + print!("{}", histogram.to_string()); + } +} diff --git a/src/util/mod.rs b/src/util/mod.rs index fe7c884..b9fa689 100644 --- a/src/util/mod.rs +++ b/src/util/mod.rs @@ -2,4 +2,6 @@ pub mod slice; pub mod status; mod slice_test; pub mod coding; -mod coding_test; \ No newline at end of file +mod coding_test; +pub mod histogram; +mod histogram_test; \ No newline at end of file -- Gitee