http://www.perlmonks.org?node_id=1055543


in reply to Re: List all different equations for a given one
in thread List all different equations for a given one

How many random numbers do you need to proof that abs($x**10000001) and abs($x**10000000) are identical? :)

Please if you consider replying that you limit the range as soon that one function returns inf think about functions with multiple separated intervals not being inf.

I'd rather avoid numerical approaches as long as possible. (IIRC for instance some differential equations can only be solved numerically)

Cheers Rolf

( addicted to the Perl Programming Language)

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Re^3: List all different equations for a given one
by BrowserUk (Patriarch) on Sep 25, 2013 at 02:15 UTC
    How many random numbers do you need {drivel} {drone}

    Not many. My first guess:

    $x = 1.000000001; say abs($x**1e8);; 1.10517092716461 $x = 1.000000001; say abs($x**(1e8+1));; 1.10517092826979

    You seem to have missed: "semi-random range" & "well-chosen set of inputs". Inspecting a string for exponentiation by big constants is trivial.

    if you consider replying that you limit the range as soon that one function returns inf think about functions with multiple separated intervals ...

    Vary them one at a time...

    I'd rather avoid ...

    You are quite welcome to do things the hard way; it seems to suite.

    The OP asked for ideas.


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