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| | Examples of scale-invariant functions are the monomials f(x)=x^n, for which , in that clearly | | Examples of scale-invariant functions are the monomials f(x)=x^n, for which , in that clearly |
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| − | 标度不变函数的实例是单项式:
| + | 许多标变函数的实例是单项式: |
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| − | <math>f(x)=x^n</math>,对于这个单项式 | + | <math>f(x)=x^n</math>, |
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| − | :<math>f(\lambda x) = (\lambda x)^n = \lambda^n f(x)~.</math>
| + | 其中 {{math|Δ {{=}} ''n''}},且有: |
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| − | :f(\lambda x) = (\lambda x)^n = \lambda^n f(x)~.
| + | <math>f(\lambda x) = (\lambda x)^n = \lambda^n f(x)~.</math> |
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| − | : f (lambda x) = (lambda x) ^ n = lambda ^ n f (x) ~ .
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| | An example of a scale-invariant curve is the [[logarithmic spiral]], a kind of curve that often appears in nature. In [[polar coordinates]] {{math|(''r'', ''θ'')}}, the spiral can be written as | | An example of a scale-invariant curve is the [[logarithmic spiral]], a kind of curve that often appears in nature. In [[polar coordinates]] {{math|(''r'', ''θ'')}}, the spiral can be written as |
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| | An example of a scale-invariant curve is the logarithmic spiral, a kind of curve that often appears in nature. In polar coordinates , the spiral can be written as | | An example of a scale-invariant curve is the logarithmic spiral, a kind of curve that often appears in nature. In polar coordinates , the spiral can be written as |
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| − | 比例不变曲线的一个例子是等角螺线,这是一种在自然界中经常出现的曲线。在极坐标系中,螺旋线可以写成
| + | 一个标度不变曲线的例子是'''Logarithmic Spiral 对数螺线(等角螺线)''',这是一种在自然界中经常出现的曲线。在极坐标系中,螺旋线可以写成 |
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| | :<math>\theta = \frac{1}{b} \ln(r/a)~.</math> | | :<math>\theta = \frac{1}{b} \ln(r/a)~.</math> |
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| − | :\theta = \frac{1}{b} \ln(r/a)~.
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| − | 1}{ b } ln (r/a) ~ .
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| | Allowing for rotations of the curve, it is invariant under all rescalings {{mvar|λ}}; that is, {{math|''θ''(''λr'')}} is identical to a rotated version of {{math|''θ''(''r'')}}. | | Allowing for rotations of the curve, it is invariant under all rescalings {{mvar|λ}}; that is, {{math|''θ''(''λr'')}} is identical to a rotated version of {{math|''θ''(''r'')}}. |
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| | Allowing for rotations of the curve, it is invariant under all rescalings ; that is, is identical to a rotated version of . | | Allowing for rotations of the curve, it is invariant under all rescalings ; that is, is identical to a rotated version of . |
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| − | 允许旋转的曲线,它是不变的所有重新标度; 也就是说,是相同的旋转版本的。
| + | 在任意重新标度{{mvar|λ}}下,标度不变也允许曲线进行旋转;换句话说,{{math|''θ''(''λr'')}}与其旋转后的{{math|''θ''(''r'')}}一模一样。 |
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| | ===Projective geometry=== | | ===Projective geometry=== |