ごくわずかな浮動小数点の値を返す（読み取り専用）。
0 との差分を持っている最小の値。
With the following rules:
- anyValue + Epsilon = anyValue
- anyValue - Epsilon = anyValue
- 0 + Epsilon = Epsilon
- 0 - Epsilon = -Epsilon
A value Between any number and Epsilon will result in an arbitrary number due to
truncating errors.
関連項目: Mathf.Approximately
no example available in C#