/**
 * Feature Extraction for Regime Detection
 *
 * Extracts features from price data for HMM training
 */
export type FeatureConfig = 'default' | string[] | number[][];
export interface FeatureExtractionOptions {
    features: FeatureConfig;
    window: number;
}
/**
 * Extract features from price data
 *
 * @param prices - Array of prices
 * @param options - Feature extraction options
 * @returns T x D matrix of standardized features
 *
 * @example
 * ```typescript
 * // Default: returns + volatility
 * const features = extractFeatures(prices, { features: 'default', window: 20 });
 *
 * // Advanced: custom feature set
 * const features = extractFeatures(prices, {
 *   features: ['returns', 'volatility', 'rsi'],
 *   window: 20
 * });
 *
 * // Custom: provide your own features
 * const features = extractFeatures(prices, {
 *   features: myCustomFeatureMatrix,
 *   window: 20
 * });
 * ```
 */
export declare function extractFeatures(prices: number[], options: FeatureExtractionOptions): number[][];