fintech-algorithms
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Percentage Volume Oscillator

Install and import#

bash
npm install fintech-algorithms
ts
import { percentageVolumeOscillator } from "fintech-algorithms/technical-indicators/volume-indicators/percentage-volume-oscillator";

Signature#

percentageVolumeOscillator(input)

Expresses the gap between a fast and a slow EMA of volume as a percentage of the slow EMA.

Parameters#

NameTypeNotes
inputTopicInputbars needs timestamp and volume. From parameters this topic reads fast_period (default 3) and slow_period (default 10, minimum fast_period + 1); period (default 14) is validated by the family but unused here.

Returns#

TopicResult

series holds a single value, 100 times the fast EMA minus the slow EMA divided by the slow EMA, and latest its last element. A bar whose slow EMA is 0 yields null rather than a division result. The warm-up is set by the slow EMA seed.

Warm-up#

The first `slow_period` - 1 bars (9 with the default 10) positions are null. ready_at is 9 on default parameters.

Errors#

  • When slow_period is not an integer greater than fast_period — throws Error
  • When fast_period is not an integer of at least 2 — throws Error
  • When a bar carries a negative volume — throws Error

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#

input
{
  "bars": [
    {
      "timestamp": "2024-01-02",
      "basis": "synthetic-unadjusted",
      "open": 100,
      "high": 101.45,
      "low": 98.695,
      "close": 100,
      "volume": 750000,
      "benchmark": 200
    },
    {
      "timestamp": "2024-01-03",
      "basis": "synthetic-unadjusted",
      "open": 101.49111452,
      "high": 103.38381693,
      "low": 100.05480022,
      "close": 101.78791214,
      "volume": 795117,
      "benchmark": 200.56326135
    },
    {
      "timestamp": "2024-01-04",
      "basis": "synthetic-unadjusted",
      "open": 102.45519048,
      "high": 104.6701838,
      "low": 100.91147007,
      "close": 102.9549389,
      "volume": 840234,
      "benchmark": 201.11020913
    }
  ],
  "parameters": {}
}

Call#

percentageVolumeOscillator(input)

Returns#

object with 9 fields: topic_id, title, state, ready, ready_at, series, latest, parameters, …

{
  "topic_id": "D07-F05-A15",
  "title": "Percentage Volume Oscillator",
  "state": "calculated",
  "ready": true,
  "ready_at": 9,
  "series": {
    "value": [null, null, null, null, null, null]
  },
  "latest": {
    "value": 2.367053666955535
  },
  "parameters": {},
  "diagnostics": {
    "causal": true,
    "input_count": 96
  }
}

Diagrams#

Percentage Volume Oscillator — article hero
Percentage Volume Oscillator — concept map
Percentage Volume Oscillator — decision comparison
Percentage Volume Oscillator — worked example

Calculation flow#

Percentage Volume Oscillator calculation flow
flowchart LR
    A["basis-consistent OHLCV observations with venue/session cov"] --> B["Validate order, basis, and finite values"]
    B --> C["Apply the selected Percentage Volume Oscillator convention"]
    C --> D["Emit value, readiness, and diagnostics"]
    D --> E["Interpret descriptively; test outcomes separately"]
    B -->|invalid or insufficient| X["Withhold output with a reason"]
Percentage Volume Oscillator readiness and evidence states
stateDiagram-v2
    [*] --> Waiting
    Waiting --> Ready: enough valid causal observations
    Waiting --> Rejected: malformed or unsupported input
    Ready --> Calculated: selected formula applied
    Calculated --> Interpreted: diagnostic and limitation retained
    Interpreted --> Ready: next observation arrives
    Rejected --> Waiting: corrected input and deterministic reset

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#

  • TA-Lib function groups — see linked primary or authoritative record
  • TA-Lib C/C++ API — see linked primary or authoritative record
  • TA-Lib maintained source — see linked primary or authoritative record
  • Evidence decision
  • Level 1 evidence map

The rest of the Volume Indicators family#