circadian_metrics
Calculates melanopic, photopic, and neuropic equivalent illuminance metrics from channel irradiances, optionally using spectral power distribution for accurate circadian lighting assessment.
Instructions
Photopic / melanopic / neuropic equivalent illuminance from channel irradiances.
Returns one metrics dict for a single point, or a list of dicts for many points. Each carries
BOTH melanopic_lux (a melanopic-weighted illuminance) and mel_edi (CIE S 026 melanopic
equivalent daylight illuminance) — they are different quantities, and the circadian standards
are written in mel-EDI, so pass mel_edi to compliance, never melanopic_lux.
spd: the SOURCE spectrum feeding these channels, when known (.spd path, 2-column text, or
[[nm, value], ...]). It is the spectrum at the LAMP, and mel_der is always reported at the
POINT: supplying it keeps the source's within-bin structure, which the channel averages cannot
represent, and combines it with the per-bin transport the channels reveal. Two extra fields come
with it — source_mel_der (the source's own) and transport_ratio (the two divided), so a room
that shifts the spectrum is visible rather than folded away. Without an SPD, mel-DER is inferred
from the channel averages alone: exact for D65, within ~1.5% for smooth spectra, up to ~8% high
for a narrow-band fluorescent. mel_der_source records which route ran.
Input Schema
| Name | Required | Description | Default |
|---|---|---|---|
| spd | No | ||
| channels | Yes | ||
| channel_type | No |
Output Schema
| Name | Required | Description | Default |
|---|---|---|---|
| result | Yes |