Module variogram 

Variogram analysis for spatial statistics

This module provides tools for variogram analysis, which is fundamental to geostatistics and spatial interpolation methods like kriging.

Features

• Experimental variogram computation - Calculate empirical variograms from data
• Theoretical variogram models - Fit standard models (spherical, exponential, Gaussian, etc.)
• Variogram fitting - Optimize model parameters
• Directional variograms - Anisotropic spatial correlation analysis
• Cross-variograms - Multivariate spatial correlation

Examples

use scirs2_core::ndarray::array;
use scirs2_spatial::variogram::{experimental_variogram, VariogramModel, fit_variogram};

// Create spatial data
let coords = array![[0.0, 0.0], [1.0, 0.0], [0.0, 1.0], [1.0, 1.0]];
let values = array![1.0, 2.0, 1.5, 2.5];

// Compute experimental variogram
let (lags, gamma) = experimental_variogram(
    &coords.view(),
    &values.view(),
    10,   // number of lag bins
    None  // automatic lag tolerance
).expect("Failed to compute variogram");

// Fit theoretical model
let model = fit_variogram(&lags, &gamma, VariogramModel::Spherical)
    .expect("Failed to fit model");

println!("Fitted parameters: range={:.2}, sill={:.2}, nugget={:.2}",
         model.range, model.sill, model.nugget);

Structs

FittedVariogram

Fitted variogram parameters

Enums

VariogramModel

Variogram model types

Functions

directional_variogram

Compute directional (anisotropic) variogram

experimental_variogram

Compute experimental (empirical) variogram from spatial data

fit_variogram

Fit a theoretical variogram model to experimental data