import numpy as np
from pathlib import Path

path = Path("sensor-readings.csv")
readings = np.array(
    [[18.25, 42.0, 0.98], [18.50, 41.5, 0.99], [18.75, 41.0, 1.01]],
    dtype=np.float64,
)

np.savetxt(
    path,
    readings,
    delimiter=",",
    header="temperature,humidity,calibration",
    comments="",
    fmt="%.2f",
)

print(path.read_text().strip())

loaded = np.loadtxt(path, delimiter=",", skiprows=1)
print("shape:", loaded.shape)
print("dtype:", loaded.dtype)
print("values match rounded export:", np.allclose(loaded, np.round(readings, 2)))