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Re: [amibroker] Re: AmiBroker 4.94.0 BETA released



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Keith,

I think I was thrown off by the stripping of extra spaces from the original post of the problem.  The post made it appear as though ELF*10 +ELF = FOOL was the problem.  If that was the case, then letters have to share values like the phone keys because F + zero = L.  

Of course if ELF + ELF = FOOL is the problem, then the solution is indeed even easier and only took a few seconds to see all the needed values for the letters.  So the problem becomes much more trivial than I thought.

E + E must generate a carry which is F

Then everything else falls out from that in 3 simple steps...

Of course this points out an important point in trading algorithms.  Brute force solutions can obscure the underlying relationships in the data.  One thinks the solution is meaningful simply because it is generated by a mathematical algorithm to complex to do by hand.  It is important to make the effort to understand the basic relationships of the data first before trying to program a profitable solution (and make sure you understand the problem you are trying to solve too!).  Otherwise you get caught in the middle of the branches of technical details and lose sight of the forest.  You end up optimizing a branch or two, not even a tree, much less the forest.  Or like me, coming up with a nifty solution for a problem nobody had.  LOL

More Fun -- Thanks,
Dennis


On May 5, 2007, at 1:10 AM, Keith McCombs wrote:

Dennis --
I don't think the problem is quite so trivial, after all it came from a math teacher.  So let's assume that Ed just forgot to pass on that no two letters have the same value.  It's still fun, and solvable, with no more work than you showed below.
-- Keith

Dennis Brown wrote:

LOL,

The brute force solution in AFL. I have solved many problems this
way with BASIC, APL, etc.

However, looking at this problem, it looks more like a logic problem
than a math problem.

You get a big hint because:
F+0 = L therefore L= F
E +0 +carry = F therefore E = F - 1
substituting you get:
c c
F-1 F F
F-1 F F
---------------------
F 2F 2F F

to make a carry: 2F > 10 therefore F>4 and O = 2F-10
L&F = 5, E = 4, O = 0
L&F = 6, E = 5, O = 2
L&F = 7, E = 6, O = 4
L&F = 8, E = 7, O = 6
L&F = 9, E = 8, O = 8

Fun one,
Dennis

On May 4, 2007, at 10:15 PM, Ed Hoopes wrote:

> AFL a powerful and flexible language - YES !
>
> A math teacher friend of mine gave me the following problem:
>
> ELF
> + ELF
> ________
>
> FOOL
>
> Each letter is an integer variable over the range 0 - 9.
> Find the values of E, L, F, O.
>
> After contemplating solving 4 equations in 4 unknowns, I decided to
> solve it by brute force with AFL. Coded as follows:
>
> // elf
> // + elf
> //_______
> // fool
>
> for (eee = 0; eee < 10; eee++)
> {
> for ( lll = 0; lll < 10; lll = lll + 2 )
> {
> for( fff = 0; fff < 10; fff++ )
> {
> elf = 100 * eee + 10 * lll + fff ;
> for (ooo = 0; ooo < 10; ooo++ )
> {
> fool = 1000*fff + 100*ooo + 10*ooo + lll;
> if(2*elf[fff] == fool[ooo])
> printf("eee= " + eee + " lll= " + lll + " fff= " + fff + " ooo= " +
> ooo + "\n" ) ;
> else
> xxx=0 ;
> }
> }
> }
> }
>
> Excuse the wrapping.
>
> AFL is GREAT !
>
> ReefBreak
>
> --- In amibroker@xxxxxxxxxps.com, "brian_z321" <brian_z321@...> wrote:
>>
>> --- In amibroker@xxxxxxxxxps.com, "jim_trades_stocks" <jnk1997@>
>> wrote:
>>>
>>> Forget about trading, making money...Baaah!, no time for that!
>>>
>>> Your mission is to keep up with the advanced functions,
>> capabilities
>>> and coding of Amibroker for a lifetime adventure of backtesting and
>>> viewing theoretical equity curves.
>>>
>>> I Guess the new evolutionary "AFL Wizard" didn't make it within 2
>>> months as was promised.
>>
>> Jim,
>>
>> No one knows how to push peoples buttons more than a sales executive.
>>
>> So you want your Formula Wizard and you want it now and you mounted a
>> public campagn to bustle Tomasz into doing it?
>>
>> I am a goer myself so I have a sneaking regard for others who have
>> balls ;-)
>>
>> Perhaps you, and others, should consider the affect that this public
>> and constant tearing away at Tomasz's persona has on him.
>>
>> He is a brilliant person but he is also human, just like us.
>>
>> On top of that you divert Tomasz's attention away from productive
>> tasks and the same applies to group members who have to come in and
>> post to provide some balance.
>>
>> Also, I think you will find there are better ways to get what you
>> want without the need for public blustering.
>>
>> I am an aggressive person but I have learnt that controlled
>> aggression, proactively directed, is the way to use that energy
>> constructively; sport is the arena where this is most apparent to any
>> observer.
>>
>> As I said in another post, I have found Tomasz very approachable, yes
>> even susceptible, to a well presented private petition.
>>
>>
>> FTR
>>
>> I have been a persistent and strong campaigner on user easy features
>> since I joined the Ami forum but a Formula Wizard does not get my
>> vote.
>> I have used them in other programs and they just don't do anything
>> for me.
>> However if Tomasz wants to do it there will be no complaints from me.
>>
>> The reason?
>>
>> I trust Tomasz's ability to steer the ship, and, aside from offering
>> no strings attached suggestions here and there I leave him to get on
>> with his job and I get on with mine.
>>
>> 55 years old has nothing to do with it.
>> Neither does *I am not trained in programming or computers*
>> *I have a full time job and a family to care for* has a lot to do
>> with it.
>>
>> I empathise with the fact that you are a road warrior; a tough career
>> choice.
>>
>> All the best for your career and your trading,
>>
>> Brian.
>>
>
>
>
>
> Please note that this group is for discussion between users only.
>
> To get support from AmiBroker please send an e-mail directly to
> SUPPORT {at} amibroker.com
>
> For NEW RELEASE ANNOUNCEMENTS and other news always check DEVLOG:
> http://www.amibroker.com/devlog/
>
> For other support material please check also:
> http://www.amibroker.com/support.html
>
> Yahoo! Groups Links
>
>
>


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Please note that this group is for discussion between users only.

To get support from AmiBroker please send an e-mail directly to
SUPPORT {at} amibroker.com

For NEW RELEASE ANNOUNCEMENTS and other news always check DEVLOG:
http://www.amibroker.com/devlog/

For other support material please check also:
http://www.amibroker.com/support.html





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