unified Z-Score

This commit is contained in:
randogoth 2024-03-01 15:45:26 +02:00
parent 517b7d55f1
commit 1189d70db1
2 changed files with 121 additions and 49 deletions

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@ -2,7 +2,7 @@ use pyo3::prelude::*;
use pyo3::types::PyList;
use pyo3::wrap_pyfunction;
use serde::Serialize;
use serde_json;
use serde_json::to_string_pretty;
#[derive(Clone, Debug, Serialize)]
struct Point {
@ -106,66 +106,77 @@ fn calculate_densities_and_gaps(dataset: &[Point], factor: f32, min_cluster_size
results
}
/// A Python-exposed function that analyzes a list of numerical values to identify clusters and significant gaps,
/// calculates z-scores for each identified cluster/gap, and returns the analysis results as a JSON string.
///
/// This function takes a list of integers (representing a dataset), a factor to adjust clustering and gap detection thresholds,
/// and a minimum cluster size. It calculates the mean distance and standard deviation across the dataset,
/// identifies clusters and significant gaps based on these metrics, calculates z-scores for each cluster/gap,
/// and returns a JSON string representing the analysis results.
/// Analyzes a dataset of integers to identify clusters and gaps, then calculates Z-scores
/// for each based on their deviation from mean metrics. The analysis aims to highlight
/// significant clusters of closely grouped points and notable gaps between them, providing
/// a statistical measure of their significance through Z-scores. The results, including
/// clusters, gaps, and their Z-scores, are serialized into a JSON string.
///
/// # Arguments
/// * `_py`: The Python interpreter, used for Python-Rust interactions. Not directly used in the function body.
/// * `int_list`: A Python list of integers representing the dataset to be analyzed.
/// * `factor`: A floating-point value used to adjust the sensitivity of cluster and gap detection.
/// Lower values result in tighter clustering and wider gaps, while higher values do the opposite.
/// * `min_cluster_size`: The minimum number of contiguous points required to be considered a cluster.
/// * `_py` - The Python interpreter instance, used for Python-Rust interoperability.
/// This argument is necessary for functions exposed to Python via PyO3 but is not
/// directly used within the function.
/// * `int_list` - A Python list of integers representing the dataset to be analyzed.
/// This list is converted into a Vec<Point> for internal processing.
/// * `factor` - A floating-point value used as a threshold factor to adjust the sensitivity
/// of cluster and gap detection. This factor influences the identification of clusters
/// by defining the minimum density or separation required.
/// * `min_cluster_size` - An integer specifying the minimum number of contiguous points
/// required for a group of points to be considered a cluster. This parameter helps
/// filter out noise by defining a threshold for the minimum cluster size.
///
/// # Returns
/// A `PyResult<String>` which is either:
/// * Ok containing a JSON-formatted string of the analysis results, including clusters and gaps with their z-scores.
/// * Err containing a Python exception if an error occurs during processing or JSON serialization.
/// Returns a `PyResult<String>` containing a JSON-formatted string of the analysis results.
/// The JSON string includes detailed information about each identified cluster and gap,
/// such as their span length, number of elements (if applicable), centroid, and calculated
/// Z-score. In case of an error during processing or serialization, a Python exception is
/// returned.
///
#[pyfunction]
fn lyagushka(_py: Python, int_list: &PyList, factor: f32, min_cluster_size: usize) -> PyResult<String> {
// Convert the Python list of integers into a Rust Vec of Point structs.
let dataset: Vec<Point> = int_list.into_iter()
.map(|py_any| py_any.extract::<u32>().map(Point::new))
.collect::<PyResult<Vec<Point>>>()?;
// Extract integers from a Python list and create a vector of Point structs.
let dataset: Vec<Point> = int_list.extract::<Vec<u32>>()?
.into_iter()
.map(Point::new)
.collect();
// Analyze the dataset to identify clusters and significant gaps.
// Calculate clusters and gaps from the dataset using predefined criteria.
let mut cluster_gap_infos = calculate_densities_and_gaps(&dataset, factor, min_cluster_size);
// Calculate the mean distance between consecutive points in the dataset.
let mean_distance: f32 = dataset.windows(2)
.map(|w| w[1].value as f32 - w[0].value as f32)
.sum::<f32>() / (dataset.len() - 1) as f32;
// Calculate the mean density of clusters in the dataset for comparison.
let mean_density: f32 = cluster_gap_infos.iter()
.filter(|info| info.num_elements > 0)
.map(|info| info.num_elements as f32 / info.span_length)
.sum::<f32>() / cluster_gap_infos.iter().filter(|info| info.num_elements > 0).count() as f32;
// Calculate the standard deviation of distances between consecutive points.
let std_deviation: f32 = (dataset.windows(2)
.map(|w| w[1].value as f32 - w[0].value as f32 - mean_distance)
.map(|d| d * d)
.sum::<f32>() / (dataset.len() - 1) as f32)
.sqrt();
// Calculate the standard deviation of cluster densities to evaluate variation.
let variance_density: f32 = cluster_gap_infos.iter()
.filter(|info| info.num_elements > 0)
.map(|info| info.num_elements as f32 / info.span_length)
.map(|density| (density - mean_density).powi(2))
.sum::<f32>() / cluster_gap_infos.iter().filter(|info| info.num_elements > 0).count() as f32;
let std_dev_density = variance_density.sqrt();
// Calculate and assign z-scores for each cluster/gap based on their centroid or span length.
for info in cluster_gap_infos.iter_mut() {
info.z_score = Some(if info.num_elements > 0 {
// For clusters, use the centroid for z-score calculation.
(info.centroid - mean_distance) / std_deviation
// Calculate the average span of all clusters and gaps to assess gap significance.
let average_span: f32 = cluster_gap_infos.iter().map(|info| info.span_length).sum::<f32>() / cluster_gap_infos.len() as f32;
// Update Z-scores for both clusters and gaps based on their deviation from mean metrics.
for info in &mut cluster_gap_infos {
if info.num_elements > 0 {
// Calculate and update Z-score for clusters based on density deviation.
let cluster_density = info.num_elements as f32 / info.span_length;
info.z_score = Some((cluster_density - mean_density) / std_dev_density);
} else {
// For gaps, use the span length for z-score calculation.
(info.span_length - mean_distance) / std_deviation
});
// Calculate and update Z-score for gaps based on span length deviation.
info.z_score = Some((info.span_length - average_span) / std_dev_density);
}
}
// Serialize the analysis results into a JSON string and return it.
serde_json::to_string_pretty(&cluster_gap_infos)
// Serialize the updated cluster and gap information, including Z-scores, to a JSON string.
to_string_pretty(&cluster_gap_infos)
.map_err(|e| PyErr::new::<pyo3::exceptions::PyException, _>(format!("JSON Serialization Error: {}", e)))
}
#[pymodule]
fn pyagushka(_py: Python, m: &PyModule) -> PyResult<()> {
m.add_function(wrap_pyfunction!(lyagushka, m)?)?;

73
test.py
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@ -1,13 +1,74 @@
from pyagushka import lyagushka
from randonautentropy import rndo
import json
import matplotlib.pyplot as plt
import numpy as np
from scipy.interpolate import interp1d
random_data = []
def generate_random_data(size=1024, max_value=100):
with open('random_values.txt', 'r') as file:
for line in file:
random_data.append(int(line.strip()))
random_data = []
max_value_bytes = (max_value.bit_length() + 7) // 8
max_int_for_bytes = 2**(max_value_bytes * 8) - 1
min_bytes_needed = max_value_bytes * size
mod_cutoff = max_int_for_bytes - (max_int_for_bytes % max_value) - 1
anomalies = json.loads(lyagushka(random_data, 1.0, 5))
# Populate the 'random_data' array
while len(random_data) < size:
hex_data = rndo.get(length=min_bytes_needed)
hex_chunks = list((hex_data[0+i:2 * max_value_bytes+i] for i in range(0, len(hex_data), 2 * max_value_bytes)))
for i in hex_chunks:
num = int(i, 16)
if num <= mod_cutoff and len(random_data) < size:
random_data.append( num % (max_value + 1) )
print(anomalies)
return random_data
# load the random test data
dataset = []
# with open('random_values.txt', 'r') as file:
# for line in file:
# random_data.append(int(line.strip()))
dataset = generate_random_data(1024, 1024)
dataset.sort()
# calculate the anomalies in the data
analysis_results = json.loads(lyagushka(dataset, 3.0, 7))
print(analysis_results)
print(len(analysis_results))
# Initialize plot
plt.figure(figsize=(10, 6))
# Plot dataset points
for point in dataset:
plt.plot(point, 0, 'ko') # Plot dataset as black dots at y=0
# Process each cluster/gap for plotting
for result in analysis_results:
if result['num_elements'] > 0: # It's a cluster
color = 'blue' # Color for clusters
else: # It's a gap
color = 'green' # Color for gaps
# Generate start and end points for the segment
start = result['centroid'] - result['span_length'] / 2
end = result['centroid'] + result['span_length'] / 2
z_score = result['z_score'] if result['z_score'] is not None else 0
# Plot a line segment for the cluster/gap
plt.plot([start, end], [z_score, z_score], color=color, linewidth=2)
# Enhancements for visualization
plt.xlabel('Integer Value')
plt.ylabel('Z-Score')
plt.title('Cluster and Gap Analysis with Distinct Z-Score Curves')
plt.grid(True)
# Custom legend
plt.plot([], [], color='blue', label='Clusters')
plt.plot([], [], color='green', label='Gaps')
plt.legend()
plt.show()