D = k·s·cos²θ(k=100)。
D = k·s·cos²θ(k=100)。
| Item | Formula / Note | Source / Standard |
|---|---|---|
| Stadia formula | D = K·l·cos²α for inclined sights, K = 100 | Classic stadia formula |
| Staff intercept | l = upper − lower stadia readings; accuracy ≈1/300 of distance | Stadia accuracy practice value |
| Height difference | h = D·tanα + i − v (instrument height i, middle reading v) | Short-distance trigonometric leveling |
| Modern alternatives | Total stations give 1–2 mm + 2 ppm; stadia only for rough surveys/checks | GB 50026-2020 EDM requirements |