Returns a diver's breathing rate measured from a logged dive: RMV (surface litres a minute, what plan_dive and gas_usage take) and SAC (pressure drop a minute on that cylinder), overall and per segment. Use this when a diver gives start and end pressures and asks their SAC, RMV or breathing rate. Give the cylinder's mix for trimix; air is assumed. Not for planning gas (gas_usage, plan_dive).
Each segment is one stretch on one cylinder: depth, duration_min, start_pressure, end_pressure, the cylinder (preset, cylinder_size, rated_pressure, twinset; default AL80) and its mix (oxygen_pct, helium_pct; default air). RMV uses the same real-gas model as the planners: any RMV plans the same dive back to the measured end pressure in plan_dive, and an air RMV does in gas_usage, which assumes air (a trimix RMV reads about 1 to 2 bar optimistic there). SAC is the gauge drop over time and depth. Segments must not overlap in time; the tool cannot check that. sac is null when the segments used different cylinders, and sac_per_cylinder lists each, with the weighted average depth. plan_dive_gas_consumption.working_sac is ready to paste into plan_dive. water defaults to en13319. No engine call.
Example: {"segments":[{"depth":20,"duration_min":20,"start_pressure":200,"end_pressure":140,"preset":"single_12l"}]}