in the past, in geodesic surveying, a system of formulas derived from spherical trigonometry was used. this method is much complicated and the precision of the results is not sufficiently high.
过去在大地测距中使用一套由球面三角导出的公式、方法较繁而精度不够高。
the mathematical models of the dynamic target and the tested apparatus are constructed with spherical trigonometry spherics.
运用球面三角学,建立了动态靶标与被测仪器间的数学模型;
until about 1450 spherical trigonometry consisted of loose rules based on greek, hindu and arabic versions .
差不多直到1450年球面三角的内容由一些不严谨的法则组成,这此法则的基础是希腊、印度和阿拉伯译本。
methods of spherical trigonometry and direction cosine matrix were applied respectively to derive the bracket error, and the two methods had the same error formula and the same calculation results.