# getMeterIntervals

> Derives the volume of every interval between consecutive readings of the same meter (.well v2.3 volume derivation, normative). Only effective (non-retracted) meterreading entries count; readings of each meter are ordered by instant, then sequence (lower first, absent first), then file order.

> **getMeterIntervals**(`well`): [`MeterInterval`](/utils/api/type-aliases/MeterInterval)[]

Derives the volume of every interval between consecutive readings of the
same meter (.well v2.3 volume derivation, normative). Only effective
(non-retracted) `meter_reading` entries count; readings of each meter are
ordered by instant, then `sequence` (lower first, absent first), then file
order.

- r₂ ≥ r₁ → r₂ − r₁.
- r₂ < r₁ with `max_reading` → (`max_reading` − r₁) + r₂ (rollover).
- r₂ < r₁ without `max_reading` → `volume: null` (unknown).

Intervals never span two meters, so a meter swap leaves the gap between
the removal and installation readings unmetered. Production before a
meter's first reading is unknown and yields no interval. Readings whose
`meter_id` does not resolve are still paired (without rollover). The result
is sorted by `end` instant.

## Parameters

### well

`Well`

## Returns

[`MeterInterval`](/utils/api/type-aliases/MeterInterval)[]