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Topic: SF: Finally, surrogate factoring
Replies: 86   Last Post: Jun 10, 2006 11:51 PM

 Messages: [ Previous | Next ]
 David Bernier Posts: 3,892 Registered: 12/13/04
Re: JSH: SF: Finally, surrogate factoring
Posted: Jun 8, 2006 6:21 AM

jstevh@msn.com wrote:
> Rick Decker wrote:
>> Tim Peters wrote:
>>> [Rick Decker]
>>>

>> <snip>
>>>
>>> [jstevh@msn.com]

>> <snip>
>>>>> But your solution has more than that because it gives
>>>>>
>>>>> y = (5f_1 - 3f_2 + 21g_1 - g_2)/4
>>>>>
>>>>> as a solution as well.

>>>
>>> [Rick Decker]
>>>

>>>> No. However, it would be interesting to see how you got this.
>> to anyone who hasn't been following closely>

>>> Are you psychic or what?
>> Yes, and I knew you'd ask that.
>>

>>> I had no idea how he came up with the thing
>>> containing 21g_1, and never would have guessed he was just pulling it out of
>>> his butt :-)

>> Surely you're not surprised.
>>>
>>>> Let h_1 and h_2 be chosen so that h_1 * h_2 = 21 * T
>>>>
>>>> h_1 + h_2 = 10*y + 42*z + 19*f_1 - 3*f_2 [1]
>>>> h_2 - h_1 = 4*y - 5*f_1 + 3*f_2 [2]

>>>
>>> I think you meant to write h_1 - h_2 on the LHS of [2].

>> Indeed I did.
>>>
>>>> Then we can write
>>>>
>>>> (10*y + 42*z + 19*f_1 - 3*f_2)^2 = (4*y - 5*f_1 + 3*f_2)^2 + 84*T
>>>>
>>>> in the form
>>>>
>>>> (h_1 + h_2)^2 = (h_1 - h_2)^2 + 4 * h_1 * h_2

>>>
>>> This part would be clearer with the correction above.

>> Yes.
>>>
>>>> Then, from [1] and [2] we solve for y to get
>>>>
>>>> y = (5*f_1 - 3*f_2 + h_1 - h_2) / 4 [3]

>>>
>>> While this conclusion _needs_ the correction above.

>> Yes, yes.
>>>
>>>> Then, since h_1 * h_2 = 21 * T = 21 * g_1 * g_2 we may as well
>>>> pick h_1 = 21 * g_1 and h_2 = g_2 so [3] becomes
>>>>
>>>> y = (5*f_1 - 3*f_2 + 21*g_1 - g_2) / 4
>>>>
>>>> Right?

>>>
>>> Yes, you are psychic!

>> I knew you'd say that.
>>>
>>>> If that was your reasoning, it's wrong. You can't pick any old
>>>> values for h_1 and h_2. Watch:
>>>>
>>>> Solving [1] and [2] for h_1 and h_2 we get
>>>>
>>>> h_1 = 7(y + 3 * z + f_1)
>>>> h_2 = 3(y + 7 * z + 4 * f_1 - f_2)

>>>
>>> That also needs the correction above ;-)

>> (Grr). Yes, yes, yes!
>>>
>>>> But from your original four linear equations we can derive
>>>>
>>>> g_1 = y + 3 * z + f_1
>>>> g_2 = y + 7 * z + 4 * f_1 - f_2
>>>>
>>>> in other words, we are forced to choose
>>>>
>>>> h_1 = 7 * g_1
>>>> h_2 = 3 * g_2
>>>>
>>>> and not your h_1 = 21 * g_1 and h_2 = g_2.

>>>
>>> And to force the conclusion, in that case [3] becomes
>>>
>>> y = (5*f_1 - 3*f_2 + 7*g_1 - 3*g_2)/4
>>>
>>>
>>> But let's give James something else to worry about :-) Take
>>>
>>> (42*z + 10*y - 3*f_2 + 19*f_1)^2 = (4*y + 3*f_2 - 5*f_1)^2 + 84*T
>>>
>>> expand it, use the quadratic equation to solve for y, and then substitute to
>>> get rid of z and T:
>>>
>>> z = -(3*f_1 - f_2 + g_1 - g_2)/4
>>> T = g_1*g_2
>>>
>>> The result is:
>>>
>>> y = (5*f_1 - 3*f_2 + 5*g_1 - 5*g_2 +/- 2*(g_1 + g_2))/4
>>>
>>> Pick "+" and you get the result James wants:
>>>
>>> y = (5*f_1 - 3*f_2 + 7*g_1 - 3*g_2)/4
>>>
>>> Pick "-" and it's different:
>>>
>>> y = (5*f_1 - 3*f_2 + 3*g_1 - 7*g_2)/4
>>>
>>> Woo hoo! Centuries of mathematics down the tubes again, or can James spot
>>> the bogosity? Hint #1: this isn't an algebraic error; you really do get
>>> that result for y. Hint #2: you get the same two results for y if you do
>>> the same thing but starting from
>>>
>>> (2*y + 10*z + 5*f_1 - f_2)^2 = (4*z + 3*f_1 - f_2)^2 + 4*T
>>>

>> Hehe. I predict that this section (cute, BTW) will generate no response.
>>>
>>>> <snip>
>>>>> I wonder if you just lied.
>>>
>>>> You just can't resist, can you? Are you naturally boorish, or do
>>>> you have to work at it?

>>>
>>> I strongly suspect that bit of gratuitous assholishness was deliberate. God
>>> only knows why, but James got it into his head that he needs to _provoke_
>>> people into replying when he thinks they know something he wants to find
>>> out. That's just his despicable way of trying to goad you into doing his
>>> work for him. It's especially idiotic in this case, since if he had any
>>> memory he'd recall that you typically respond much better to polite requests
>>> than to his stupid baiting tactics.
>>>
>>> But, in this case, I'm afraid what he'll take away is "ha! it worked again",
>>> without a shadow of a clue that it was neither necessary nor helpful to
>>> behave like an ass.
>>>

>> Sadly, I predict you're right again.
>>
>>
>> Regards,
>>
>> Rick

>
> You're both lying.
>
> I am going to warn you.
>
> Neither of you will live to see 2007 because of this lie becaue there
> will be angry people who will kill you, as there is so much money at
> stake.
>
> Billions will be lost.
>
> It's not like you can reverse it now either.
>
> You killed yourselves.
>
> It might have seemed like a small lie to both of you, but your names
> will live in infamy, while you will not live at all.
>
>
> James Harris
>

priceless

Date Subject Author
6/4/06 JAMES HARRIS
6/5/06 Doug Schwarz
6/5/06 Tim Peters
6/5/06 Doug Schwarz
6/5/06 Christopher J. Henrich
6/5/06 Gib Bogle
6/5/06 Proginoskes
6/5/06 William L. Bahn
6/5/06 JAMES HARRIS
6/5/06 Abstract Dissonance
6/5/06 Abstract Dissonance
6/5/06 Salami Man
6/5/06 William L. Bahn
6/6/06 Brian Quincy Hutchings
6/5/06 guenther.vonKnakspott@gmx.de
6/6/06 Matthijs Hebly
6/6/06 Salami Man
6/5/06 Abstract Dissonance
6/5/06 Gordon Burditt
6/5/06 Sebastian Gottschalk
6/5/06 dkguru
6/5/06 Ed Weir \(ComCast\)
6/5/06 Abstract Dissonance
6/5/06 Andrew Swallow
6/5/06 gjedwards@gmail.com
6/5/06 Salami Man
6/5/06 Gib Bogle
6/6/06 TC
6/6/06 Salami Man
6/5/06 Sebastian Gottschalk
6/5/06 JAMES HARRIS
6/5/06 marc.t.davies@gmail.com
6/5/06 gjedwards@gmail.com
6/5/06 LarryLard
6/5/06 William L. Bahn
6/5/06 Richard Henry
6/5/06 Salami Man
6/5/06 Bob Marlow
6/5/06 Bob Marlow
6/5/06 none
6/5/06 rossum
6/5/06 Rick Decker
6/5/06 JAMES HARRIS
6/5/06 jshsucks@yahoo.com
6/5/06 Salami Man
6/5/06 Tim Peters
6/5/06 JAMES HARRIS
6/5/06 Tim Peters
6/6/06 Rick Decker
6/6/06 Rick Decker
6/6/06 Tim Peters
6/6/06 Rick Decker
6/7/06 David C. Ullrich
6/7/06 Rick Decker
6/7/06 Jesse F. Hughes
6/7/06 Rick Decker
6/8/06 David C. Ullrich
6/7/06 Bertie Reed
6/6/06 JAMES HARRIS
6/6/06 JAMES HARRIS
6/7/06 Rick Decker
6/7/06 Tim Peters
6/7/06 Rick Decker
6/8/06 JAMES HARRIS
6/8/06 Jose Carlos Santos
6/8/06 Rick Decker
6/8/06 LarryLard
6/8/06 David Bernier
6/8/06 Rick Decker
6/9/06 Tim Peters
6/9/06 david250@gmail.com
6/9/06 marcus_b
6/8/06 Richard Henry
6/8/06 jshsucks@yahoo.com
6/8/06 Paul Sperry
6/8/06 LarryLard
6/8/06 Denis Feldmann
6/8/06 David Bernier
6/8/06 David C. Ullrich
6/8/06 David Moran
6/8/06 David Bernier
6/8/06 Tim Peters
6/8/06 Proginoskes
6/10/06 Tim Peters
6/10/06 Tim Peters
6/6/06 gjedwards@gmail.com
6/6/06 Proginoskes