/**
 * @param {string} name
 * @param {any | any[]} [fields]
 * @param {any | any[]} [params]
 */
export function op(name: string, fields?: any | any[], params?: any | any[]): Op;
export class Op {
    constructor(name: any, fields: any, params: any);
    name: any;
    fields: any;
    params: any;
    toString(): string;
    toObject(): {
        expr: string;
        func: boolean;
    };
}
export function any(field: any): Op;
export function count(): Op;
export function array_agg(field: any): Op;
export function array_agg_distinct(field: any): Op;
export function map_agg(key: any, value: any): Op;
export function object_agg(key: any, value: any): Op;
export function entries_agg(key: any, value: any): Op;
/**
 * @typedef {import('../table/types.js').Struct} Struct
 */
/**
 * All table expression operations including normal functions,
 * aggregate functions, and window functions.
 */
export const opApi: {
    /**
     * Generate an object representing the current table row.
     * @param {...string} names The column names to include in the object.
     *  If unspecified, all columns are included.
     * @return {Struct} The generated row object.
     */
    row_object: (...names: string[]) => Struct;
    /**
     * Aggregate function to count the number of records (rows).
     * @returns {number} The count of records.
     */
    count: () => Op;
    /**
     * Aggregate function returning an arbitrary observed value.
     * @template T
     * @param {T} field The data field.
     * @return {T} An arbitrary observed value.
     */
    any: (field: any) => Op;
    /**
     * Aggregate function to collect an array of values.
     * @template T
     * @param {T} field The data field.
     * @return {Array<T>} A list of values.
     */
    array_agg: (field: any) => Op;
    /**
     * Aggregate function to collect an array of distinct (unique) values.
     * @template T
     * @param {T} field The data field.
     * @return {Array<T>} An array of unique values.
     */
    array_agg_distinct: (field: any) => Op;
    /**
     * Aggregate function to create an object given input key and value fields.
     * @template K, V
     * @param {K} key The object key field.
     * @param {V} value The object value field.
     * @return {Record<K, V>} An object of key-value pairs.
     */
    object_agg: (key: any, value: any) => Op;
    /**
     * Aggregate function to create a Map given input key and value fields.
     * @template K, V
     * @param {K} key The object key field.
     * @param {V} value The object value field.
     * @return {Map<K, V>} A Map of key-value pairs.
     */
    map_agg: (key: any, value: any) => Op;
    /**
     * Aggregate function to create an array in the style of Object.entries()
     * given input key and value fields.
     * @template K, V
     * @param {K} key The object key field.
     * @param {V} value The object value field.
     * @return {[K, V][]} An array of [key, value] arrays.
     */
    entries_agg: (key: any, value: any) => Op;
    /**
     * Aggregate function to count the number of valid values.
     * Invalid values are null, undefined, or NaN.
     * @param {*} field The data field.
     * @return {number} The count of valid values.
     */
    valid: (field: any) => number;
    /**
     * Aggregate function to count the number of invalid values.
     * Invalid values are null, undefined, or NaN.
     * @param {*} field The data field.
     * @return {number} The count of invalid values.
     */
    invalid: (field: any) => number;
    /**
     * Aggregate function to count the number of distinct values.
     * @param {*} field The data field.
     * @return {number} The count of distinct values.
     */
    distinct: (field: any) => number;
    /**
     * Aggregate function to determine the mode (most frequent) value.
     * @template T
     * @param {T} field The data field.
     * @return {T} The mode value.
     */
    mode: <T>(field: T) => T;
    /**
     * Aggregate function to sum values.
     * @param {*} field The data field.
     * @return {number} The sum of the values.
     */
    sum: (field: any) => number;
    /**
     * Aggregate function to multiply values.
     * @param {*} field The data field.
     * @return {number} The product of the values.
     */
    product: (field: any) => number;
    /**
     * Aggregate function for the mean (average) value.
     * @param {*} field The data field.
     * @return {number} The mean (average) of the values.
     */
    mean: (field: any) => number;
    /**
     * Aggregate function for the average (mean) value.
     * @param {*} field The data field.
     * @return {number} The average (mean) of the values.
     */
    average: (field: any) => number;
    /**
     * Aggregate function for the sample variance.
     * @param {*} field The data field.
     * @return {number} The sample variance of the values.
     */
    variance: (field: any) => number;
    /**
     * Aggregate function for the population variance.
     * @param {*} field The data field.
     * @return {number} The population variance of the values.
     */
    variancep: (field: any) => number;
    /**
     * Aggregate function for the sample standard deviation.
     * @param {*} field The data field.
     * @return {number} The sample standard deviation of the values.
     */
    stdev: (field: any) => number;
    /**
     * Aggregate function for the population standard deviation.
     * @param {*} field The data field.
     * @return {number} The population standard deviation of the values.
     */
    stdevp: (field: any) => number;
    /**
     * Aggregate function for the minimum value.
     * @template T
     * @param {T} field The data field.
     * @return {T} The minimum value.
     */
    min: <T>(field: T) => T;
    /**
     * Aggregate function for the maximum value.
     * @template T
     * @param {T} field The data field.
     * @return {T} The maximum value.
     */
    max: <T>(field: T) => T;
    /**
     * Aggregate function to compute the quantile boundary
     * of a data field for a probability threshold.
     * @param {*} field The data field.
     * @param {number} p The probability threshold.
     * @return {number} The quantile value.
     */
    quantile: (field: any, p: number) => number;
    /**
     * Aggregate function for the median value.
     * This is a shorthand for the 0.5 quantile value.
     * @param {*} field The data field.
     * @return {number} The median value.
     */
    median: (field: any) => number;
    /**
     * Aggregate function for the sample covariance between two variables.
     * @param {*} field1 The first data field.
     * @param {*} field2 The second data field.
     * @return {number} The sample covariance of the values.
     */
    covariance: (field1: any, field2: any) => number;
    /**
     * Aggregate function for the population covariance between two variables.
     * @param {*} field1 The first data field.
     * @param {*} field2 The second data field.
     * @return {number} The population covariance of the values.
     */
    covariancep: (field1: any, field2: any) => number;
    /**
     * Aggregate function for the product-moment correlation between two variables.
     * To instead compute a rank correlation, compute the average ranks for each
     * variable and then apply this function to the result.
     * @param {*} field1 The first data field.
     * @param {*} field2 The second data field.
     * @return {number} The correlation between the field values.
     */
    corr: (field1: any, field2: any) => number;
    /**
     * Aggregate function for calculating a binning scheme in terms of
     * the minimum bin boundary, maximum bin boundary, and step size.
     * @param {*} field The data field.
     * @param {number} [maxbins=15] The maximum number of allowed bins.
     * @param {boolean} [nice=true] Flag indicating if the bin min and max
     *  should snap to "nice" human-friendly values.
     * @param {number} [minstep] The minimum allowed step size between bins.
     * @param {number} [step] The exact step size to use between bins.
     *  If specified, the maxbins and minstep arguments are ignored.
     * @return {[number, number, number]} The bin [min, max, and step] values.
     */
    bins: (field: any, maxbins?: number, nice?: boolean, minstep?: number, step?: number) => [number, number, number];
    /**
     * Window function to assign consecutive row numbers, starting from 1.
     * @return {number} The row number value.
     */
    row_number: () => number;
    /**
     * Window function to assign a rank to each value in a group, starting
     * from 1. Peer values are assigned the same rank. Subsequent ranks
     * reflect the number of prior values: if the first two values tie for
     * rank 1, the third value is assigned rank 3.
     * @return {number} The rank value.
     */
    rank: () => number;
    /**
     * Window function to assign a fractional (average) rank to each value in
     * a group, starting from 1. Peer values are assigned the average of their
     * indices: if the first two values tie, both will be assigned rank 1.5.
     * @return {number} The peer-averaged rank value.
     */
    avg_rank: () => number;
    /**
     * Window function to assign a dense rank to each value in a group,
     * starting from 1. Peer values are assigned the same rank. Subsequent
     * ranks do not reflect the number of prior values: if the first two
     * values tie for rank 1, the third value is assigned rank 2.
     * @return {number} The dense rank value.
     */
    dense_rank: () => number;
    /**
     * Window function to assign a percentage rank to each value in a group.
     * The percent is calculated as (rank - 1) / (group_size - 1).
     * @return {number} The percentage rank value.
     */
    percent_rank: () => number;
    /**
     * Window function to assign a cumulative distribution value between 0 and 1
     * to each value in a group.
     * @return {number} The cumulative distribution value.
     */
    cume_dist: () => number;
    /**
     * Window function to assign a quantile (e.g., percentile) value to each
     * value in a group. Accepts an integer parameter indicating the number of
     * buckets to use (e.g., 100 for percentiles, 5 for quintiles).
     * @param {number} num The number of buckets for ntile calculation.
     * @return {number} The quantile value.
     */
    ntile: (num: number) => number;
    /**
     * Window function to assign a value that precedes the current value by
     * a specified number of positions. If no such value exists, returns a
     * default value instead.
     * @template T
     * @param {T} field The data field.
     * @param {number} [offset=1] The lag offset from the current value.
     * @param {T} [defaultValue=undefined] The default value.
     * @return {T} The lagging value.
     */
    lag: <T>(field: T, offset?: number, defaultValue?: T) => T;
    /**
     * Window function to assign a value that follows the current value by
     * a specified number of positions. If no such value exists, returns a
     * default value instead.
     * @template T
     * @param {T} field The data field.
     * @param {number} [offset=1] The lead offset from the current value.
     * @param {T} [defaultValue=undefined] The default value.
     * @return {T} The leading value.
     */
    lead: <T>(field: T, offset?: number, defaultValue?: T) => T;
    /**
     * Window function to assign the first value in a sliding window frame.
     * @template T
     * @param {T} field The data field.
     * @return {T} The first value in the current frame.
     */
    first_value: <T>(field: T) => T;
    /**
     * Window function to assign the last value in a sliding window frame.
     * @template T
     * @param {T} field The data field.
     * @return {T} The last value in the current frame.
     */
    last_value: <T>(field: T) => T;
    /**
     * Window function to assign the nth value in a sliding window frame
     * (counting from 1), or undefined if no such value exists.
     * @template T
     * @param {T} field The data field.
     * @param {number} nth The nth position, starting from 1.
     * @return {T} The nth value in the current frame.
     */
    nth_value: <T>(field: T, nth: number) => T;
    /**
     * Window function to fill in missing values with preceding values.
     * @template T
     * @param {T} field The data field.
     * @param {T} [defaultValue=undefined] The default value.
     * @return {T} The current value if valid, otherwise the first preceding
     *  valid value. If no such value exists, returns the default value.
     */
    fill_down: <T>(field: T, defaultValue?: T) => T;
    /**
     * Window function to fill in missing values with subsequent values.
     * @template T
     * @param {T} field The data field.
     * @param {T} [defaultValue=undefined] The default value.
     * @return {T} The current value if valid, otherwise the first subsequent
     *  valid value. If no such value exists, returns the default value.
     */
    fill_up: <T>(field: T, defaultValue?: T) => T;
    parse_date(value: any): Date;
    parse_float(value: any): number;
    parse_int(value: any, radix?: number): number;
    endswith(value: any, search: string, length?: number): boolean;
    match(value: any, regexp: any, index: number | string): string | string[];
    normalize(value: any, form: string): string;
    padend(value: any, length: number, fill?: string): string;
    padstart(value: any, length: number, fill?: string): string;
    upper(value: any): string;
    lower(value: any): string;
    repeat(value: any, number: any): string;
    replace(value: any, pattern: any, replacement: any): string;
    split(value: any, separator: any, limit?: number): string[];
    startswith(value: any, search: string, position?: number): boolean;
    substring(value: any, start?: number, end?: number): string;
    trim(value: any): string;
    has<K extends string | number, V>(object: Map<K, V> | Set<K> | Record<K, V>, key: K): boolean;
    keys<K extends string | number, V>(object: Map<K, V> | Record<K, V>): K[];
    values<K extends string | number, V>(object: Map<K, V> | Set<V> | Record<K, V>): V[];
    entries<K extends string | number, V>(object: Map<K, V> | Set<V> | Record<K, V>): [K, V][];
    object<K extends string | number, V>(entries: Iterable<[K, V]>): Record<K, V>;
    random(): number;
    is_nan(value: any): boolean;
    is_finite(value: any): boolean;
    abs(value: number): number;
    cbrt(value: number): number;
    ceil(value: number): number;
    clz32(value: number): number;
    exp(value: number): number;
    expm1(value: number): number;
    floor(value: number): number;
    fround(value: number): number;
    greatest(...values: number[]): number;
    least(...values: number[]): number;
    log(value: number): number;
    log10(value: number): number;
    log1p(value: number): number;
    log2(value: number): number;
    pow(base: number, exponent: number): number;
    round(value: number): number;
    sign(value: number): number;
    sqrt(value: number): number;
    trunc(value: number): number;
    degrees(radians: number): number;
    radians(degrees: number): number;
    acos(value: number): number;
    acosh(value: number): number;
    asin(value: number): number;
    asinh(value: number): number;
    atan(value: number): number;
    atan2(y: number, x: number): number;
    atanh(value: number): number;
    cos(value: number): number;
    cosh(value: number): number;
    sin(value: number): number;
    sinh(value: number): number;
    tan(value: number): number;
    tanh(value: number): number;
    parse_json(value: string): any;
    to_json(value: any): string;
    format_date(date: Date | number, shorten?: boolean): string;
    format_utcdate(date: Date | number, shorten?: boolean): string;
    now(): number;
    timestamp(date: Date | number): number;
    datetime(year?: number, month?: number, date?: number, hours?: number, minutes?: number, seconds?: number, milliseconds?: number, ...args: any[]): Date;
    year(date: Date | number): number;
    quarter(date: Date | number): number;
    month(date: Date | number): number;
    week(date: Date | number, firstday: number): number;
    date(date: Date | number): number;
    dayofyear(date: Date | number): number;
    dayofweek(date: Date | number): number;
    hours(date: Date | number): number;
    minutes(date: Date | number): number;
    seconds(date: Date | number): number;
    milliseconds(date: Date | number): number;
    utcdatetime(year?: number, month?: number, date?: number, hours?: number, minutes?: number, seconds?: number, milliseconds?: number, ...args: any[]): Date;
    utcyear(date: Date | number): number;
    utcquarter(date: Date | number): number;
    utcmonth(date: Date | number): number;
    utcweek(date: Date | number, firstday: number): number;
    utcdate(date: Date | number): number;
    utcdayofyear(date: Date | number): number;
    utcdayofweek(date: Date | number): number;
    utchours(date: Date | number): number;
    utcminutes(date: Date | number): number;
    utcseconds(date: Date | number): number;
    utcmilliseconds(date: Date | number): number;
    compact<T>(array: T[]): T[];
    concat<T>(...values: (T | T[])[]): T[];
    includes<T>(sequence: T[], value: T, index?: number): boolean;
    indexof<T>(sequence: T[] | string, value: T): number;
    join<T>(array: T[], delim: string): string;
    lastindexof<T>(sequence: T[] | string, value: T): number;
    length(sequence: any[] | string): number;
    pluck(array: any[], property: string): any[];
    reverse<T>(sequence: T[] | string): T[] | string;
    slice<T>(sequence: T[] | string, start?: number, end?: number): T[] | string;
    bin: typeof import("./functions/bin.js").bin;
    equal: typeof import("./functions/equal.js").equal;
    recode: typeof import("./functions/recode.js").recode;
    sequence: typeof import("./functions/sequence.js").sequence;
};
export type Struct = import("../table/types.js").Struct;