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Thanks but I would still need to first convert output to AFL from the
string. The expressions are dependent on the arrays within AB.
The only workaround would be to one day program the whole thing in
AFL. But I think that offloading it to a C++ program was the way to
go, as it is runs as compiled code, quite fast.
And by dynamically writing strings to the include file, I am hoping it
will still be speedy. Will know in a few days after reworking the DLL
and testing.
--- In amibroker@xxxxxxxxxxxxxxx, "Paul Ho" <paul.tsho@xxx> wrote:
>
> Since the strings are generated from the dll, presumably from a set of
> tokens, Depending on how it is written, the logic used in writing
the string
> can be extended to evaluate the string as well. why dont you ask the
> programmer to do that.
>
>
> On Thu, Nov 27, 2008 at 12:52 PM, ozzyapeman <zoopfree@xxx> wrote:
>
> > Thanks again, TJ. I had not even considered dynamically writing
to an
> > include file. That might do it.
> >
> > Since I already paid to have the DLL coded, and it outputs strings, a
> > small modification will allow it to output both the left AND right
> > side of the variable expression.
> >
> > Then for each optimization step, I will have the formula FPUT to the
> > include file, then read back from that file - and thus cycle through
> > thousands of expressions with only a SINGLE expression in my main
formula.
> >
> > Yes, the expressions are already generated from functions, but in C++.
> > I thought it would run faster that way, rather than trying to code it
> > all in AFL - hence the DLL. The examples I gave were substitutions for
> > the real expressions, which are much more complex.
> >
> > --- In amibroker@xxxxxxxxxxxxxxx <amibroker%40yahoogroups.com>,
"Tomasz
> > Janeczko" <groups@> wrote:
> > >
> > > The point is that you don't need to include thousands of
expressions
> > > but only ONE !
> > > If you change the CONTENT of include file dynamically by writing TO
> > the file you can
> > > have dynamic expression evaluation.
> > > And all that without any DLL.
> > >
> > > Also it all really depends on what you are specifically trying
to do.
> > > General descriptions lack clarity. You need to provide ENTIRE idea
> > with details
> > > if you want help. Otherwise people are guessing what you are trying
> > to do.
> > >
> > > For example if you want to SWITCH between different conditions in
> > run time
> > > the SWITCH structure gives fastest execution:
> > >
> > > switch( n )
> > > {
> > > case 1:
> > > result = MA(C, 12) > C5 AND MA(C,20) < Close;
> > > break;
> > > case 2:
> > > result = MA(H, 50) < C12 AND EMA(L, 12) < Close;
> > > break;
> > > default:
> > > break;
> > > }
> > >
> > >
> > > It is fast because on ONE of Nth expressions will be actually
evaluated.
> > >
> > > There are other techniques that lead to compact and fast formula
> > > but it ALL depends on details on what exactly you want to do.
> > > For example I can see that your expressions are repeated with only
> > > minor fluctuations (replacing C with H) and that can be easily
wrapped
> > > into functions / switch statements provided one has clear idea
> > > and knows what he wants to achieve and prepares plan for that.
> > >
> > > The general rule is first THINK a lot before writing the very first
> > line of code.
> > > If you begin with just typing thousands of lines of code without
> > planning first you end up with spaghetti.
> > >
> > > Best regards,
> > > Tomasz Janeczko
> > > amibroker.com
> > > ----- Original Message -----
> > > From: "ozzyapeman" <zoopfree@>
> > > To: <amibroker@xxxxxxxxxxxxxxx <amibroker%40yahoogroups.com>>
> > > Sent: Thursday, November 27, 2008 1:07 AM
> > > Subject: [amibroker] Re: How to convert a string to non-string
> > characters?!
> > >
> > >
> > > > Thanks, TJ. Looks like I am back at square one. I contracted
to have
> > > > the DLL coded because pasting the thousands of expressions at once
> > > > into the formula slowed down AB considerably. Most of the time it
> > > > hung. So I was trying to generate the expressions dynamically.
> > > >
> > > > Correct me if I am wrong, but wouldn't the #include function
result in
> > > > overall execution that is slower than pasting the thousands of AFL
> > > > expressions directly into the formula?
> > > >
> > > > Or will it actually be faster than a copy and paste?
> > > >
> > > > In some cases I am trying to evaluate tens of thousands of
full blown
> > > > AFL expressions per formula.
> > > >
> > > >
> > > > --- In amibroker@xxxxxxxxxxxxxxx <amibroker%40yahoogroups.com>,
> > "Tomasz Janeczko" <groups@> wrote:
> > > >>
> > > >> Hello,
> > > >>
> > > >> You need to understand that you are attempting to PARSE
expressions.
> > > >>
> > > >> The only way to parse actual full-blown AFL expressions is to
> > > > INCLUDE them
> > > >> in the formula.
> > > >>
> > > >> If you want to "create" expressions on the fly AND execute them,
> > > >> you need to take two step approach
> > > >> a) create TEXT file with actual expressions you want to parse
> > > >> b) #include that text file
> > > >>
> > > >> #pragma nocache
> > > >> #include "the_file_with_the_expressions_to_parse"
> > > >>
> > > >> in the actual formula and run it.
> > > >>
> > > >> Best regards,
> > > >> Tomasz Janeczko
> > > >> amibroker.com
> > > >> ----- Original Message -----
> > > >> From: "ozzyapeman" <zoopfree@>
> > > >> To: <amibroker@xxxxxxxxxxxxxxx <amibroker%40yahoogroups.com>>
> > > >> Sent: Thursday, November 27, 2008 12:38 AM
> > > >> Subject: [amibroker] Re: How to convert a string to non-string
> > > > characters?!
> > > >>
> > > >>
> > > >> > TJ,
> > > >> >
> > > >> > Thanks, quick question:
> > > >> >
> > > >> > I gave the arithmetic expression as a quick trivial example.
> > But what
> > > >> > I really want to do is create and evaluate expressions of
the type:
> > > >> >
> > > >> > Condition1 = MA(C, 12) > C5 AND MA(C,20) < Close;
> > > >> >
> > > >> > so for the above case, would you also recommend writing a
> > > >> > parser/interpreter - or did you suggest that purely for
arithmetic
> > > >> > expressions like "1 + 2 + 3"?
> > > >> >
> > > >> >
> > > >> > --- In amibroker@xxxxxxxxxxxxxxx <amibroker%40yahoogroups.com>,
> > "Tomasz Janeczko" <groups@>
> > wrote:
> > > >> >>
> > > >> >> You do not want to convert from string to number.
> > > >> >> What you really want is to EVALUATE arithmetic expressions !
> > > >> >> For that you need to either write parser/interpreter or use
> > > >> > external onee
> > > >> >> Thanks to AmiBroker JScript support you can use for example
> > JScript
> > > >> > eval function.
> > > >> >>
> > > >> >>
> > > >> >> EnableScript("JScript");
> > > >> >> <%
> > > >> >>
> > > >> >> %>
> > > >> >>
> > > >> >> function Evaluate( text )
> > > >> >> {
> > > >> >> so = GetScriptObject();
> > > >> >> return so.eval( text );
> > > >> >> }
> > > >> >>
> > > >> >> "The result is " + Evaluate("3 + 2");
> > > >> >>
> > > >> >> Best regards,
> > > >> >> Tomasz Janeczko
> > > >> >> amibroker.com
> > > >> >> ----- Original Message -----
> > > >> >> From: ozzyapeman
> > > >> >> To: amibroker@xxxxxxxxxxxxxxx <amibroker%40yahoogroups.com>
> > > >> >> Sent: Wednesday, November 26, 2008 11:46 PM
> > > >> >> Subject: [amibroker] Re: How to convert a string to non-string
> > > >> > characters?!
> > > >> >>
> > > >> >>
> > > >> >> Or to take a more trivial example, the following prints "3"
> > > >> > instead of "12":
> > > >> >>
> > > >> >> VarSetText("Condition1", "3 + 4 + 5");
> > > >> >>
> > > >> >> Total = StrToNum (VarGetText("Condition1"));
> > > >> >>
> > > >> >> printf ("Sum %g", Total);
> > > >> >>
> > > >> >> How do I convert the above string so that Total is equal
to the
> > > >> > expression itself, which is equal to 12?
> > > >> >>
> > > >> >>
> > > >> >> --- In amibroker@xxxxxxxxxxxxxxx
<amibroker%40yahoogroups.com>,
> > "ozzyapeman" <zoopfree@>
> > wrote:
> > > >> >> >
> > > >> >> > Yes, tried that. But since the values spit out by the
function
> > > >> > aren't
> > > >> >> > just pure numbers, it does not seem to work.
> > > >> >> >
> > > >> >>
> > > >> >
> > > >> >
> > > >> >
> > > >> > ------------------------------------
> > > >> >
> > > >> > **** IMPORTANT ****
> > > >> > This group is for the discussion between users only.
> > > >> > This is *NOT* technical support channel.
> > > >> >
> > > >> > *********************
> > > >> > TO GET TECHNICAL 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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> > > >> >
> > > >> >
> > > >>
> > > >
> > > >
> > > >
> > > > ------------------------------------
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> > > > This group is for the discussion between users only.
> > > > This is *NOT* technical support channel.
> > > >
> > > > *********************
> > > > TO GET TECHNICAL SUPPORT from AmiBroker please send an e-mail
> > directly to
> > > > SUPPORT {at} amibroker.com
> > > > *********************
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> > > > For NEW RELEASE ANNOUNCEMENTS and other news always check DEVLOG:
> > > > http://www.amibroker.com/devlog/
> > > >
> > > > For other support material please check also:
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> > > > Yahoo! Groups Links
> > > >
> > > >
> > > >
> > >
> >
> >
> >
>
------------------------------------
**** IMPORTANT ****
This group is for the discussion between users only.
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*********************
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SUPPORT {at} amibroker.com
*********************
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For other support material please check also:
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