※ 引述《inuy (一歩一步前进中)》之铭言：
: ※ 引述《Yyh (我爱批踢踢)》之铭言：
: : If A is invertible, we can get x by "solve(A,b)".
: : what if A is not invertible?
: : Is anyone have good ideas?
: SVD
Can we just use 'lsfit' ?
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Description of lsfit:
The least squares estimate of *b* in the model
y = X b + e
is found.
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