出典:Wikipedia
出典:『Wikipedia』 (2011/04/27 11:20 UTC 版)
In the study of ellipses and related geometry, various parameters in the distortion of a circle into an ellipse are identified and employed: Aspect ratio, flattening and eccentricity. All of these parameters are ultimately trigonometric functions of the ellipse's modular angle, or angular eccentricity, the conventional denotation being the Greek letter "alpha",
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