Ellips
洛 2023/1/10
gma 内置的椭球体位于 crs.Ellips 模块下。内置椭球体参数如下：
| 椭球体名称 | 长半轴（m） | 反扁率 |
|---|---|---|
| Airy1830 | 6377563.396 | 299.3249646 |
| AiryModified1849 | 6377340.189 | 299.3249646 |
| AustralianNationalSpheroid | 6378160 | 298.25 |
| AverageTerrestrialSystem1977 | 6378135 | 298.257 |
| Bessel1841 | 6377397.155 | 299.1528128 |
| BesselModified | 6377492.018 | 299.1528128 |
| BesselNamibia | 6377483.865 | 299.1528128 |
| CGCS2000 | 6378137 | 298.2572221 |
| Clarke1858 | 6378293.645 | 294.2606764 |
| Clarke1866 | 6378206.4 | 294.9786982 |
| Clarke1880 | 6378306.37 | 293.4663077 |
| Clarke1880ARC | 6378249.145 | 293.4663077 |
| Clarke1880Benoit | 6378249.145 | 293.4663077 |
| Clarke1880ING | 6378249.2 | 293.4660213 |
| Clarke1880INTFoot | 6378300.789 | 293.4663155 |
| Clarke1880RGS | 6378249.145 | 293.465 |
| Danish1876 | 6377019.27 | 300 |
| Everest1830Definition | 6377299.366 | 300.8017255 |
| Everest1830Modified | 6377304.063 | 300.8017 |
| GRS1967 | 6378160 | 298.2471674 |
| GRS1967Modified | 6378160 | 298.25 |
| GRS1980 | 6378137 | 298.2572221 |
| GSK2011 | 6378136.5 | 298.2564151 |
| Helmert1906 | 6378200 | 298.3 |
| Hough1960 | 6378270 | 297 |
| IAG1975 | 6378140 | 298.257 |
| IndonesianNationalSpheroid | 6378160 | 298.247 |
| International1924 | 6378388 | 297 |
| Krassowsky1940 | 6378245 | 298.3 |
| NWL9D | 6378145 | 298.25 |
| PZ90 | 6378136 | 298.2578393 |
| Plessis1817 | 6376523 | 308.64 |
| Struve1860 | 6378298.3 | 294.73 |
| WGS72 | 6378135 | 298.26 |
| WGS84 | 6378137 | 298.2572236 |
| WarOffice | 6378300 | 296 |
示例：
from gma import crs
Ellips = crs.Ellips.Airy1830
print(Ellips)
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>>> {'SemiMajor': 6377563.396, 'InvFlattening': 299.3249646}