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Hi - off the top of my head, untested...
for( i = 1; i <= 10; i++ )
{
for( j = 1; j <= 10; j++ )
{
VarSet( "Matrix" + "Row" + i + "Col" + j, i * j );
}
}
----- Original Message -----
From: "brian_z111" <brian_z111@xxxxxxxxx>
To: <amibroker@xxxxxxxxxxxxxxx>
Sent: Tuesday, March 24, 2009 11:38 AM
Subject: [amibroker] Re: AFL 101
> Yes, I understand the distinction between array and multi-dimensional
> arrays and I appreciate ABs' capabilities in the speed with which it
> handles arrays.
>
>> I can understand your difficulties but the fact that you don't
>> >understand something
>> or don't know how to use some functionality, does not mean that it >does
>> not exist nor that it is not useful.
>
> Yes, that is true (except for the difficulties part ... I am not having
> any difficulties .... happy to discuss the pros and cons of AB for the
> benefit of newcomers though).
>
>> I sincerely appreciate your willingness to teach me what array is, >and
>> what can be considered array function and what not.
>
> I don't know about that.
>
> Really I think it us just an interesting and educational discussion and
> other 101'ers must have got something out of it (possibly they found the
> Wiki link relevant too).
>
> Once again I thank you for a very good educational post.
>
>
> Re VarSet/VarGet:
>
> You have mentioned using them to produce dynamic arrays before (in this
> forum I think) BUT the help manual doesn't say anything about the
> possibility in using them that way .... it indicates that the function
> only accepts a value (singular) for the argument and the example uses only
> a single value .... unless you changed something in the beta (I don't use
> beta releases ... I wait for the new version upgrade + manual).
>
> How could I use VarSet to create an array of arrays?
>
>
> VARSET
> - sets the value of dynamic variable Miscellaneous functions
> (AFL 2.60)
>
>
> SYNTAX VarSet( ''varname'', value )
> RETURNS NUMBER
> FUNCTION Sets the value of dynamic variable. Returns 1 on success, 0 on
> failure.
> Dynamic variables are variables that are named dynamically, typically by
> creating a variable name from a static part and a variable part. The
> following example dynamically constructs the variable name from a variable
> prefix and a static suffix.
>
> EXAMPLE for( i = 1; i < 10; i++ )
> {
> VarSet( "C"+i, Ref( C, -i ) );
> }
>
> // creates variables C1, C2, C3, C4, ...., C10 equal to Ref( C, -1 ),
> Ref( C, -2 ), ..., Ref( C, -10 )
> // respectively
>
>
>
>
>
>
>
> --- In amibroker@xxxxxxxxxxxxxxx, "Tomasz Janeczko" <groups@xxx> wrote:
>>
>> Hello,
>>
>> Sorry, but it is complete waste of time to discuss basics and wikipedia
>> refs.
>> You are mixing terms and you don't really understand what I am saying.
>>
>> FWIW: matrix is not the same array, at least not in the meaning I used in
>> the post.
>> When I speak about array - I mean one dimensional array (vector) the only
>> one that is
>> directly representable in computer (linear) memory.
>> And array are of course natively supported in AFL (unlike other languages
>> that DO NOT feature
>> array operations (you can not use simply operator + to add arrays
>> (element by element) in other general purpose languages).
>> Matrix is 2 and higher dimension - the "array of the array(s)"
>>
>> (FWIW: MATLAB, IDL, S-lang are NOT general purpose languages. General
>> purpose languages
>> are those in which actual applications are written, i.e. C, C++, Java,
>> Basic, Pascal, etc).
>>
>> Your response clearly shows that you don't even know what you want
>> (see "very good for developers/instutions and the handful of traders who
>> want to write their own trading program [...]
>> hardly what the average trader wants to have to do before they can start
>> trading" in the response
>> to me pointing out direct database read/write interface that you claimed
>> does not exist ).
>>
>>
>> I can understand your difficulties but the fact that you don't understand
>> something
>> or don't know how to use some functionality, does not mean that it does
>> not exist nor that it is not useful.
>> Some things simply require learning and time to "sink in". Take your time
>> and you will see enourmous
>> possibilities existing in AFL and will understand that the limit is only
>> your imagination.
>>
>> I sincerely appreciate your willingness to teach me what array is, and
>> what can be considered array function and what not,
>> what is native function or not, but as far as I remember I wrote
>> AmiBroker myself so probably, I know a little about all that
>> already.
>>
>> Best regards,
>> Tomasz Janeczko
>> amibroker.com
>> ----- Original Message -----
>> From: "brian_z111" <brian_z111@xxx>
>> To: <amibroker@xxxxxxxxxxxxxxx>
>> Sent: Tuesday, March 24, 2009 2:27 PM
>> Subject: [amibroker] Re: AFL 101
>>
>>
>> > Hello Tomasz,
>> >
>> > Thanks for your educational post, I thoroughly enjoyed it.
>> >
>> > Quirky != bad;
>> >
>> > (some people like quirkiness ... like Bob Dylan in his song "Simple
>> > Twist of Fate")
>> >
>> > Of course I am just giving an opinion from my perspective (personal).
>> >
>> > Re your points:
>> >
>> > C language - I was just quoting from one of your posts .... I should
>> > have given the link because you did include some context
>> >
>> > http://finance.groups.yahoo.com/group/amibroker/message/135059
>> >
>> >> As for "matrix" operations - that this does not belong to the
>> >> >definition of any general purpose language.
>> >
>> > I did a little bit of reading on 'languages that have array functions'
>> > when we had a short discussion on array programming before
>> > and found this link:
>> >
>> > http://en.wikipedia.org/wiki/Comparison_of_programming_languages_(array)
>> >
>> > (it comes from the Wikipedia array page)
>> >
>> > http://en.wikipedia.org/wiki/Array
>> >
>> > As I said, there is no point in comparing AFL to a GP language .... it
>> > is quirky to me that AFL is an array language and doesn't
>> > have a full suite of array functions .... perhaps other languages that
>> > are intended to handle price arrays etc would be a better
>> > comparison.
>> >
>> >> Having said that, for anyone needing multiple dimensional arrays in
>> >> AFL there are several options:
>> >
>> >> a) use VarGet/VarSet (the 2-dim array is simply array of the array, so
>> >> for N:M 2-dim array you need N AFL arrays)
>> >> b) using embedded JScript parts with AFL
>> >> c) using free open source Osaka plugin (you can extend it to your
>> >> needs since all sources are available)
>> >> d) using any external COM object (written in VB for example if you
>> >> need that)
>> >
>> > Except for a) none of these meet the criteria of "Native" to the
>> > language (AFL)
>> >
>> > VarGet/VarSet can hardly be described as a suite of array functions.
>> >
>> >
>> > Neither a, b, c or d achieve your own stated objective:
>> >
>> >> SIMPLICITY OF USE plus compactness of code is the paramount design
>> >> >decision.
>> >
>> >> The database is exposed in two ways:
>> >> First (more general)
>> >> full OLE read/write direct access to the database - see
>> >> Stocks/Stock/Quotations/Quotation objects:
>> >> http://www.amibroker.com/guide/objects.html
>> >> - and this OLE interface is DIRECTLY available from AFL level.
>> >
>> >
>> > That is very good for developers/instutions and the handful of traders
>> > who want to write their own trading program built around
>> > AB.
>> >
>> >
>> .
>> >
>> > Anyway, all of this could be done much easier from within AFL using AFL
>> > functions .... there is no need at all to use OLE for this
>> > type of thing .... it seems like overkill to me for a simple array
>> > processing language.
>> >
>> >
>> >
>> >> Second (easier)
>> >> AddToComposite/Foreign - gives you easy to use way to STORE and >READ
>> >> from the AmiBroker database.
>> >
>> > ATC is time dependent ... when timeframe compression is used it starts
>> > to become quirky and that is just the beginning.
>> >
>> > Once again hardly a substitute for a full suite of native database
>> > functions.
>> >
>> >
>> > --- In amibroker@xxxxxxxxxxxxxxx, "Tomasz Janeczko" <groups@> wrote:
>> >>
>> >> Hello,
>> >>
>> >> There are several misconceptions in what was written here.
>> >> AFL is specifically designed to protect the newbie and people without
>> >> coding experience
>> >> from programming stuff like memory allocation/deallocation, pointer
>> >> manipulation,
>> >> declarations, type casting, etc.
>> >>
>> >> So although it looks like C it is way more easy than C.
>> >>
>> >> What is single operator in AFL (like array addition) involves many
>> >> line of code in C
>> >> plus memory allocation/deallocation (and keeping track on all that).
>> >>
>> >> SIMPLICITY OF USE plus compactness of code is the paramount design
>> >> decision.
>> >> That's why arrays in AFL are automatically managed, have size that
>> >> automatically
>> >> refers to "visible" area, so you can simply add arrays with single +
>> >> operator.
>> >>
>> >> With general purpose C language with "normal" arrays you would need to
>> >> manage memory for arrays by yourself,
>> >> alignment (if size differs which elements to add), looping (you need
>> >> to perform calculations
>> >> on individual elements of array).
>> >> (maybe you don't know but in C and there are no built-in dynamic
>> >> arrays, only fixed compile-time size is supported,
>> >> and dynamic array is implemented via pointers and explicit memory
>> >> allocation malloc/free)
>> >>
>> >> As for "matrix" operations - that this does not belong to the
>> >> definition of any general purpose language.
>> >>
>> >> There are no "matrix" operations in any popular general purpose
>> >> language C/C++/Java/JScript/Basic/Pascal.
>> >>
>> >> In C/C++ even scalar trigonometric operations like sin( x) or string
>> >> concatenation are NOT part of the language.
>> >>
>> >> The language itself defines:
>> >> a) syntax
>> >> b) basic arithmetic operators + precedence working on primitive types
>> >> only (scalar integer and/or float)
>> >> c) flow control (conditional execution, loops)
>> >> d) structural concepts
>> >> (variables/functions/procedures/structures/objects)
>> >> e) some miscellaneous stuff like run-time type info, exception
>> >> handling etc.
>> >>
>> >> And that's it.
>> >>
>> >> Anything more is supplied by LIBRARIES. In C there is a library for
>> >> basic string manipulation (such as concatenation
>> >> - strcat) or floating point. The same with any high-level stuff like
>> >> matrices - this is the area which
>> >> is implemented by EXTERNAL libraries (not part of the language).
>> >> Libraries in AFL can be provided by:
>> >> a) #include - the AFL code implementing features via functions
>> >> b) AmiBroker Development Kit - allowing to write extensions
>> >> (functions) as a DLL in any compiled language.
>> >> c) JScript/VBScript
>> >> d) any external COM object
>> >> http://www.amibroker.com/guide/a_aflcom.html
>> >>
>> >> This covers any imaginable application and any imaginable need you may
>> >> have.
>> >>
>> >> Having said that, for anyone needing multiple dimensional arrays in
>> >> AFL there are several options:
>> >> a) use VarGet/VarSet (the 2-dim array is simply array of the array, so
>> >> for N:M 2-dim array you need N AFL arrays)
>> >> b) using embedded JScript parts with AFL
>> >> c) using free open source Osaka plugin (you can extend it to your
>> >> needs since all sources are available)
>> >> d) using any external COM object (written in VB for example if you
>> >> need that)
>> >>
>> >> If anyone is "advanced enough" to need multiple dimensional arrays, it
>> >> is also "advanced enough" to use these options
>> >> without any trouble.
>> >>
>> >>
>> >> Also with regards to:
>> >> > - some of the architecture of AB is quirky also e.g. essentially it
>> >> > is a database, at the binary level, but you can't write
>> >> > directly to the native database
>> >> That is entirely not true.
>> >> The database is exposed in two ways:
>> >> First (more general)
>> >> full OLE read/write direct access to the database - see
>> >> Stocks/Stock/Quotations/Quotation objects:
>> >> http://www.amibroker.com/guide/objects.html
>> >> - and this OLE interface is DIRECTLY available from AFL level.
>> >>
>> >> Second (easier)
>> >> AddToComposite/Foreign - gives you easy to use way to STORE and READ
>> >> from the AmiBroker database.
>> >>
>> >> Best regards,
>> >> Tomasz Janeczko
>> >> amibroker.com
>> >> ----- Original Message -----
>> >> From: "brian_z111" <brian_z111@>
>> >> To: <amibroker@xxxxxxxxxxxxxxx>
>> >> Sent: Tuesday, March 24, 2009 1:46 AM
>> >> Subject: [amibroker] Re: AFL 101
>> >>
>> >>
>> >> > My perspective as a newcomer to programming when I started into
>> >> > AB/AFL around 2-3 years ago:
>> >> >
>> >> > - Tomasz says that AB is most like C
>> >> > - primarily one has to learn AFL fullstop
>> >> > - experienced programmers sometimes have to unlearn somethings and
>> >> > find this hard to do for a while
>> >> > - in some ways programming naivity paid off for me as I am at home
>> >> > with array programming
>> >> > - in other places I am lost because nothing can fill the missing
>> >> > link of not being familiar with syntax that is common to other
>> >> > languages (called experience)
>> >> > - AFL is quirky ..... some things that intuitively and logically
>> >> > seem needed are 'missing' and then you have to work around
>> >> > that
>> >> > e.g. IMO it is bizarre that AFL has been around for many years but
>> >> > doesn't have dynamic arrays or matrix functions ... the
>> >> > quirky
>> >> > aspects of AFL make it extremely difficult for lay people ... every
>> >> > time you get on a roll you find an exception
>> >> > - some of the architecture of AB is quirky also e.g. essentially it
>> >> > is a database, at the binary level, but you can't write
>> >> > directly to the native database
>> >> > - to save you future distress....many in the past have asked for an
>> >> > AFL book...the logic seems compelling to me
>> >> > - everyone starts from a different place so some need an 'Intro to
>> >> > AB', book
>> >> > - I like Howards contributions overall but IMO it is rather old
>> >> > world to publish in hard copy ... an ebook would be much better
>> >> > ... we have to consider that AB/AFL is way beyond the 500 pages
>> >> > allocated to it ib Howard's 2 books.
>> >> > - the AFL library is not the place to learn code ... good for
>> >> > sharing code between experienced AFL'ers
>> >> > - this forum is a book and contains at least 1000* the code, help,
>> >> > code and trading tips available anywhere else .....
>> >> > unfortunately it lacks sections, an index and topics etc .... once
>> >> > again the logic for a better forum (from an educational
>> >> > perspective) seems compelling.
>> >> >
>> >> > (Sorry Rik but Google searching Yahoo doesn't reference threads does
>> >> > it?)
>> >> >
>> >> > - AB/AFL is huge ... I don't think any layperson will ever cover it
>> >> > all without a big effort to become a programming expert,
>> >> > albeit one who specialises in AFL
>> >> >
>> >> > - AB is not a democracy or an open project
>> >> >
>> >> > BTW all of the advice given in this thread so far is spot on.
>> >> >
>> >> >
>> >> >
>> >> >
>> >> >
>> >> > --- In amibroker@xxxxxxxxxxxxxxx, "louies88" <Louies88@> wrote:
>> >> >>
>> >> >> I think Amibroker is great, especially its AFL. Although I don't
>> >> >> know enough about it to claim that it's superior than most
>> >> >> other
>> >> >> scripting languages out there, I know for a fact that this is one
>> >> >> of the best. That also begs the question of how a person w/
>> >> >> virtually no programming background can get started w/ AFL. I
>> >> >> followed this forum long enough to note that some of you in here
>> >> >> are excellent coders. The codes that I often see are flawless and
>> >> >> eloquent, which then makes me think how long does it take a
>> >> >> coding newbie such as myself to attain that coding level.
>> >> >>
>> >> >> I look at it this way. Coding a computer language is pretty similar
>> >> >> to learning a foreign language. I remember how my first
>> >> >> English class went. I started out by learning a few basic
>> >> >> vocabulary words, then use some of it in the form of a noun, then a
>> >> >> verb, finally an object. Sentence structures, or in computer
>> >> >> language better known as syntax, govern if a sentence is
>> >> >> grammatically correct or if it's not. With that in mind, I also
>> >> >> started out by looking at the AFL Library in Amibroker. I
>> >> >> downloaded all of the functions in the hope of building myself an
>> >> >> Amibroker vocabulary and started to put some of the basic
>> >> >> vocabulary words together to make a "sentence."
>> >> >>
>> >> >> However, since there isn't any kind of document FORMALLY teaching
>> >> >> the ABC of coding in Amibroker, I'm left w/ a question how
>> >> >> does
>> >> >> Amibroker syntax work? Some of the experienced coders here often
>> >> >> compare AFL syntax to that of C++. But for a person w/
>> >> >> neither
>> >> >> background in AFL or C++ or any other computer langugae, the
>> >> >> question remains: How do I get start? Where's the square one?
>> >> >>
>> >> >> Anybody w/ such experience is highly appreciated if he/she's
>> >> >> willing to shed a light on this.
>> >> >>
>> >> >>
>> >> >> Thanks
>> >> >>
>> >> >
>> >> >
>> >> >
>> >> >
>> >> > ------------------------------------
>> >> >
>> >> > **** IMPORTANT PLEASE READ ****
>> >> > This group is for the discussion between users only.
>> >> > This is *NOT* technical support channel.
>> >> >
>> >> > TO GET TECHNICAL SUPPORT send an e-mail directly to
>> >> > SUPPORT {at} amibroker.com
>> >> >
>> >> > TO SUBMIT SUGGESTIONS please use FEEDBACK CENTER at
>> >> > http://www.amibroker.com/feedback/
>> >> > (submissions sent via other channels won't be considered)
>> >> >
>> >> > For NEW RELEASE ANNOUNCEMENTS and other news always check DEVLOG:
>> >> > http://www.amibroker.com/devlog/
>> >> >
>> >> > Yahoo! Groups Links
>> >> >
>> >> >
>> >> >
>> >>
>> >
>> >
>> >
>> >
>> > ------------------------------------
>> >
>> > **** IMPORTANT PLEASE READ ****
>> > This group is for the discussion between users only.
>> > This is *NOT* technical support channel.
>> >
>> > TO GET TECHNICAL SUPPORT send an e-mail directly to
>> > SUPPORT {at} amibroker.com
>> >
>> > TO SUBMIT SUGGESTIONS please use FEEDBACK CENTER at
>> > http://www.amibroker.com/feedback/
>> > (submissions sent via other channels won't be considered)
>> >
>> > For NEW RELEASE ANNOUNCEMENTS and other news always check DEVLOG:
>> > http://www.amibroker.com/devlog/
>> >
>> > Yahoo! Groups Links
>> >
>> >
>> >
>>
>
>
>
>
> ------------------------------------
>
> **** IMPORTANT PLEASE READ ****
> This group is for the discussion between users only.
> This is *NOT* technical support channel.
>
> TO GET TECHNICAL SUPPORT send an e-mail directly to
> SUPPORT {at} amibroker.com
>
> TO SUBMIT SUGGESTIONS please use FEEDBACK CENTER at
> http://www.amibroker.com/feedback/
> (submissions sent via other channels won't be considered)
>
> For NEW RELEASE ANNOUNCEMENTS and other news always check DEVLOG:
> http://www.amibroker.com/devlog/
>
> Yahoo! Groups Links
>
>
>
>
------------------------------------
**** IMPORTANT PLEASE READ ****
This group is for the discussion between users only.
This is *NOT* technical support channel.
TO GET TECHNICAL SUPPORT send an e-mail directly to
SUPPORT {at} amibroker.com
TO SUBMIT SUGGESTIONS please use FEEDBACK CENTER at
http://www.amibroker.com/feedback/
(submissions sent via other channels won't be considered)
For NEW RELEASE ANNOUNCEMENTS and other news always check DEVLOG:
http://www.amibroker.com/devlog/
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