hyperbola

An equalarea pseudo cylindrical projection gather is constructed, in which the longitudes are hyperbola being symmetrical to the central meridian and the latitudes are parallel lines.

摘要构建了一个纬象平行于赤道的直，经象对称于中央直经的双曲，且面积没有变形的投影集合，并得到一组概括公式。

Results The difference values calculated were various with the arch form, the sequence was oval, round, parabola, catenuliform, and hyperbola from big difference to smell.

牙弓深度的差值按从大到小的顺序：椭圆形、圆形、抛物形、悬链形、双曲形。