import { CovarianceMatrixOptions } from '../schemas/CovarianceMatrixOptionsSchema';
import { CovarianceMatrixResult } from '../schemas/CovarianceMatrixResultSchema';
/**
 * Calculate Covariance Matrix
 *
 * Cov(X,Y) = E[(X - μ_X)(Y - μ_Y)]
 *
 * Measures how two variables move together.
 * Diagonal = variances
 * Off-diagonal = covariances
 *
 * @param options - Array of return series and optional labels
 * @returns Covariance matrix with variances
 */
export declare function calculateCovarianceMatrix(options: CovarianceMatrixOptions): CovarianceMatrixResult;