The assumption that Ptolemy adopted star coordinates from a star catalog by Hipparchus is investigated based on Hipparchus’ equatorial star coordinates in his Commentary on the phenomena of Aratus and Eudoxus . Since Hipparchus’ catalog was presumably based on an equatorial coordinate system, his star positions must have been converted into the ecliptical system of Ptolemy’s catalog in his Almagest . By means of a statistical analysis method, data groups consistent with this conversion of coordinates are identified. The found groups show a high degree of agreement between Hipparchus’ and Ptolemy’s data. The value of the obliquity of the ecliptic underlying the conversion is estimated by adjustment and statistically agrees with Ptolemy’s value of this parameter. The results allow the assumption that Ptolemy’s coordinates were determined from Hipparchus’ coordinates by an accurate star globe or even by calculation. For a calculative derivation of ecliptical coordinates from equatorial ones, possible calculation methods are discussed considering the mathematics of the Almagest .

中文翻译：

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论托勒密星表的制作

托勒密从喜帕恰斯星表中采用星坐标的假设是根据喜帕恰斯在他对阿拉图斯和欧多克索斯现象的评论中的赤道星坐标进行的研究。由于喜帕恰斯的星表大概是基于赤道坐标系，所以他的恒星位置一定已经转换成托勒密星表中的黄道系。通过统计分析方法，识别符合这种坐标转换的数据组。发现的组显示喜帕恰斯和托勒密的数据高度一致。转换所依据的黄道倾角值是通过调整估计的，并且在统计上与托勒密的该参数值一致。结果允许假设托勒密的坐标是由喜帕恰斯的坐标通过精确的星球甚至通过计算确定的。为了从赤道坐标计算推导黄道坐标，考虑到 Almagest 的数学，讨论了可能的计算方法。