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octant n.1.八分圓;八分區;卦限;八分儀;【植物;植物學】八...

octarchy

The three axes determine three planes , the - , - and - plane . which divide space into eight octants . to each pointin space corresponds an ordered triple of numbers . its cartesian coordinates , which measure its directed distances from the three planes 三個坐標決定三個坐標面,面,面,面,這些坐標面將空間分成八個卦限,空間中點每個點都對應一個有序三元組和分別表示點到三個坐標面的有向距離

In each iteration , no trigonometric function is used and only two multiplications are required . by taking the advantage of symmetry , only the points in one octant are need to be generated 該算法避免三角函數的運算,每步僅需兩次乘法,并且充分利用對稱性只計算一個八分象限的點。

Early introduction and studies on the western double reflecting octant in china 中國早期對西方雙反射八分儀的介紹和研究