CmDsOfdmConstellationDisplay — downstream OFDM constellation display

Parser and helper for DOCSIS downstream OFDM constellation snapshots captured in the CmDsOfdmConstellationDisplay PNM format.

Module location src/pypnm/pnm/parser/CmDsOfdmConstellationDisplay.py

Inputs

• Binary payload produced by the cable modem when requesting a constellation display capture (see FastAPI single-capture guide).
• Optional DecimalPrecision parameters to control rounding when exposing values.

Outputs

CmDsOfdmConstellationDisplayModel exposes:

• header: metadata (capture time, modulation profile, etc.).
• points: list of [real, imag] coordinates per subcarrier.
• dimensions: axes scaling for plotting helpers.

Usage

from pathlib import Path
from pypnm.pnm.parser.CmDsOfdmConstellationDisplay import CmDsOfdmConstellationDisplay

payload = Path("constellation.bin").read_bytes()
constellation = CmDsOfdmConstellationDisplay(payload)

points = constellation.get_points()  # [[real, imag], ...]
header = constellation.get_header()