[SciPy-User] could you explain the line_search method?

[devdoer bird]

HI:

Sorry to post here if it's  not a  proper question.

I'm reading the source code of line_search function in optimize.py , and
there's a statement to compute the initial step alpha , listed below:



alpha1 = pymin(1.0, 1.01*2*(phi0-old_old_fval)/derphi0)


I don't what's the physical meaning of 1.01*2*(phi0-old_old_fval)/derphi0,

Can some one give me some explaination?

Thanks!
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