/**
 * Element-wise addition.
 * - If `b` is a number, returns `a + b` for each element.
 * - If `b` is an array, returns element-wise sum up to the shorter length.
 * @param a Left operand array
 * @param b Right operand array or scalar
 * @returns Float64Array of sums
 */
export declare function add(a: ArrayLike<number>, b: ArrayLike<number> | number): Float64Array;
/**
 * Element-wise subtraction.
 * - If `b` is a number, returns `a - b` for each element.
 * - If `b` is an array, returns element-wise difference up to the shorter length.
 * @param a Left operand array
 * @param b Right operand array or scalar
 * @returns Float64Array of differences
 */
export declare function sub(a: ArrayLike<number>, b: ArrayLike<number> | number): Float64Array;
/**
 * Element-wise multiplication.
 * - If `b` is a number, scales each element of `a` by `b`.
 * - If `b` is an array, returns element-wise products up to the shorter length.
 * @param a Left operand array
 * @param b Right operand array or scalar
 * @returns Float64Array of products
 */
export declare function mul(a: ArrayLike<number>, b: ArrayLike<number> | number): Float64Array;
/**
 * Element-wise division.
 * - If `b` is a number, divides each element of `a` by `b`.
 * - If `b` is an array, returns element-wise quotients up to the shorter length.
 * @param a Numerator array
 * @param b Denominator array or scalar
 * @returns Float64Array of quotients
 */
export declare function div(a: ArrayLike<number>, b: ArrayLike<number> | number): Float64Array;
/**
 * Element-wise average: (a + b) / 2.
 * Computes the average without allocating temporaries.
 * @param a First array
 * @param b Second array or scalar
 * @returns Float64Array of averages
 */
export declare function avg(a: ArrayLike<number>, b: ArrayLike<number> | number): Float64Array;
/**
 * Scale an array by a scalar: `source * s`.
 * @param source Input array
 * @param s Scale factor
 * @returns Float64Array scaled values
 */
export declare function scale(source: ArrayLike<number>, s: number): Float64Array;
/**
 * Clamp values to the inclusive range [lo, hi]. Preserves NaN entries.
 * @param source Input array
 * @param lo Lower bound
 * @param hi Upper bound
 * @returns Float64Array with values clamped or NaN preserved
 */
export declare function clamp(source: ArrayLike<number>, lo: number, hi: number): Float64Array;
/**
 * Element-wise absolute value.
 * @param source Input array
 * @returns Float64Array of absolute values
 */
export declare function abs(source: ArrayLike<number>): Float64Array;
/**
 * Element-wise sign (-1, 0, 1) for each entry.
 * @param source Input array
 * @returns Float64Array of sign values
 */
export declare function sign(source: ArrayLike<number>): Float64Array;
/**
 * Round values to nearest integer. Ties are rounded away from zero.
 * @param source Input array
 * @returns Float64Array of rounded integers
 */
export declare function round(source: ArrayLike<number>): Float64Array;
/**
 * Element-wise floor operation.
 * @param source Input array
 * @returns Float64Array of floored values
 */
export declare function floor(source: ArrayLike<number>): Float64Array;
/**
 * Element-wise ceil operation.
 * @param source Input array
 * @returns Float64Array of ceiled values
 */
export declare function ceil(source: ArrayLike<number>): Float64Array;
/**
 * First difference: output[i] = source[i] - source[i-1].
 * The first element is NaN (no previous value).
 * @param source Input array
 * @returns Float64Array of differences (first element NaN)
 */
export declare function diff(source: ArrayLike<number>): Float64Array;
/**
 * Map a callback across `source` producing a new Float64Array.
 * @param source Input array
 * @param cb Mapping callback `(value, index, array) => number`
 * @returns Float64Array of mapped values
 */
export declare function apply(source: ArrayLike<number>, cb: (v: number, i: number, arr: ArrayLike<number>) => number): Float64Array;
/**
 * Apply a callback to each element in `source` in-place.
 * Modifies the provided array.
 * @param source Mutable array to update
 * @param cb Callback `(value, index) => newValue`
 */
export declare function applyInPlace(source: number[] | Float64Array, cb: (value: number, index: number) => number): void;
/**
 * Element-wise less-than comparison. Returns `Uint8Array` mask with 1 where true.
 * @param a Left operand
 * @param b Right operand or scalar
 * @returns Uint8Array mask of comparisons
 */
export declare function lt(a: ArrayLike<number>, b: ArrayLike<number> | number): Uint8Array;
/**
 * Element-wise less-than-or-equal comparison (with epsilon tolerance).
 * @param a Left operand
 * @param b Right operand or scalar
 * @returns Uint8Array mask of comparisons
 */
export declare function lte(a: ArrayLike<number>, b: ArrayLike<number> | number): Uint8Array;
/**
 * Element-wise greater-than comparison. Returns `Uint8Array` mask with 1 where true.
 * @param a Left operand
 * @param b Right operand or scalar
 * @returns Uint8Array mask of comparisons
 */
export declare function gt(a: ArrayLike<number>, b: ArrayLike<number> | number): Uint8Array;
/**
 * Element-wise greater-than-or-equal comparison (with epsilon tolerance).
 * @param a Left operand
 * @param b Right operand or scalar
 * @returns Uint8Array mask of comparisons
 */
export declare function gte(a: ArrayLike<number>, b: ArrayLike<number> | number): Uint8Array;
/**
 * Element-wise equality comparison using `Number.EPSILON` tolerance.
 * @param a Left operand
 * @param b Right operand or scalar
 * @returns Uint8Array mask of equality tests
 */
export declare function eq(a: ArrayLike<number>, b: ArrayLike<number> | number): Uint8Array;
/**
 * Element-wise inequality comparison.
 * @param a Left operand
 * @param b Right operand or scalar
 * @returns Uint8Array mask where elements are not equal
 */
export declare function neq(a: ArrayLike<number>, b: ArrayLike<number> | number): Uint8Array;
/**
 * Logical AND for boolean masks (Uint8Array) or with a scalar.
 * Returns a Uint8Array of 1/0 values.
 * @param a Left boolean mask
 * @param b Right boolean mask or scalar
 * @returns Uint8Array mask result
 */
export declare function and(a: Uint8Array, b: Uint8Array | number): Uint8Array;
/**
 * Logical OR for boolean masks (Uint8Array) or with a scalar.
 * Returns a Uint8Array of 1/0 values.
 * @param a Left boolean mask
 * @param b Right boolean mask or scalar
 * @returns Uint8Array mask result
 */
export declare function or(a: Uint8Array, b: Uint8Array | number): Uint8Array;
/**
 * Logical NOT for a boolean mask (Uint8Array).
 * @param a Input boolean mask
 * @returns Uint8Array mask with bits inverted
 */
export declare function not(a: Uint8Array): Uint8Array;