Money Flow Index

Install and import

bash

npm install fintech-algorithms

import { money_flow_index } from "fintech-algorithms/technical-indicators/volume-indicators/money-flow-index";

Signature

money_flow_index(high, low, close, volume, p)

RSI computed on typical price weighted by volume — commonly described as volume-weighted RSI, and read on the same 0–100 scale.

Parameters

Name	Type	Notes
`high`	`number[]`	Per-bar high prices, chronological.
`low`	`number[]`	Per-bar low prices, chronological.
`close`	`number[]`	Per-bar closing prices, chronological.
`volume`	`number[]`	Per-bar traded volume, aligned index-for-index with the price series.
`p`	`number`	Lookback in bars. min: 1 · integer: true

Returns

Record<string, (number | null)[]> · length same-as-input

Parallel series: typical_price, raw_money_flow, positive_flow, negative_flow, money_flow_ratio and mfi.

Warm-up

The first p positions are null. One extra bar is needed beyond the window, because the first bar has no prior typical price to compare against.

Errors

When p < 1 or is not an integer — throws RangeError
When the input series are not all the same length — throws RangeError

Complexity: time O(n), space O(n).

Worked example

executed Captured by running this function on the input its own test provides. Real output of real code — but not asserted against a published figure.

Input

high

[101.05, 101.52482, 102.098461, 102.729464, 103.36806, 103.963227]

Showing 6 of 120 elements.

low

[99.4, 99.462904, 99.936275, 100.512674, 101.151059, 101.802588]

Showing 6 of 120 elements.

[100.28, 100.686113, 101.200346, 101.789282, 102.408843, 103.010585]

Showing 6 of 120 elements.

volume

[990000, 1066468.036, 1130033.236, 1170141.961, 1180511.26, 1160272.794]

Showing 6 of 120 elements.

Call

money_flow_index(high, low, close, volume, p)

Returns

object with 6 fields: typical_price, raw_money_flow, positive_flow, negative_flow, money_flow_ratio, mfi

{
  "typical_price": [
    100.24333333333334,
    100.55794566666668,
    101.07836066666668,
    101.67714000000001,
    102.30932066666666,
    102.92546666666668
  ],
  "raw_money_flow": [
    99240900,
    107241834.81932473,
    114221906.99372847,
    118976687.98847154,
    120777305.0499507,
    119421618.78308721
  ],
  "positive_flow": [null, null, null, null, null, null],
  "negative_flow": [null, null, null, null, null, null],
  "money_flow_ratio": [null, null, null, null, null, null],
  "mfi": [null, null, null, null, null, null]
}

Other exports

This module also exports obv, accumulation_distribution_line, chaikin_money_flow, volume_price_trend, force_index. Every module additionally exports run as an alias of its primary function, and a meta object carrying its catalog id, domain, family, shape and article URL.

Diagrams

Money Flow Index — money flow index comparison

Money Flow Index — money flow index mechanism

How it works

This page states the contract — how to call it correctly. The article explains the concept: why it works, and where it breaks.

Read the article →

References

Money Flow (MFI) — TradingView
Volume — TradingView
TA-Lib function API and volume indicators — TA-Lib
Consolidated Tape — U.S. Securities and Exchange Commission, Investor.gov
Closing Price — U.S. Securities and Exchange Commission, Investor.gov
What is Volume? — CME Group
TA-Lib momentum indicator functions — TA-Lib
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