PseudoInverse
 Usage
• PseudoInverse[m]求一个矩阵的伪逆。
Notes
• PseudoInverse 对符号和数值矩阵都可以使用。 • 对数值矩阵，PseudoInverse[m, Tolerance -> t]指定去掉小于最大奇异值的t倍的奇异值。 • 缺省设置 Tolerance -> Automatic 典型的取t为  ,其中p是输入的数值精度。 • 对非奇异方阵  ，伪逆  等于标准逆。 • 参见 Mathematica 全书 : 节 3.7.10.
 Further Examples
The pseudoinverse of a matrix m, usually denoted by  , has the property that the sum of the squares of the entries of  is minimized, where  is an identity matrix of the appropriate size.
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For invertible matrices, the pseudoinverse is the same as the inverse.
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You can compute the pseudoinverse of a non-square matrix.
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Here is another pseudoinverse.
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Here is another pseudoinverse. We use use Chop to get rid of the fuzz.
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We use use Chop to get rid of the fuzz.
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