Hi Mike,
Thanks again.
Pity about the variable operator. I don't have any problems with "if" and
"iif" statements, in this instance it just seems a bit inelegant. The sort of
extensibility I am chasing will probably be done best with a switch statement.
I've got the code running now - I used if statments in the following way:
if (something)
clause1 = xxxx >= yyyy;
else
clause1 = xxxx < yyyy;
BuyCondition = clause1 AND clause2;
Thanks for your help
Robert Z
________________________________
From: Mike <sfclimb...@yahoo.com>
To: amibroker@yahoogroups.com
Sent: Thursday, 30 July, 2009 2:16:57 PM
Subject: [amibroker] Re: Relational Operators assigned to variables?
Robert,
I don't believe that you can do the variable operator. However, it seems
like you would need to do an 'if' or 'iff' regardless. If you just want
to get the details out of your face, you can replace your variable
operator concept with function calls. You could even move the function
declarations to a separate file and just #include them.
e.g.
function myOp(something) {
return iif(something, ref(open, -x) >= ref(close, -y), ref(open, -x) <
ref(close, -y);
}
giving:
BuyCondition = myOp(something) AND myOp2(something) ...
Or, to generalize further, pass the arguments too:
function myOp(something, arg1, arg2) {
return iif(something, arg1 >= arg2, arg1 < arg2);
}
giving:
BuyCondition = myOp(something, ref(open, -x), ref(close, -y)) AND ...
Mike
--- In amibro...@yahoogrou ps.com, i cs <ics4...@... > wrote:
>
> Hi Mike,
>
> Thanks for your reply. I'm sure that I can get something happening
with a bunch of if/iif statements. I've been trying to avoid it because
I think it'll complicate the code and make it less extensible. To give
you an idea of what I'm attempting, I'm currently experimenting with the
WFA engine and running some dubious code, but the reason for this code
is NOT to write a strategy, it's to understand and get some experiential
feel for the WFA.
>
> My code is more similar to the following:
>
> if ( something )
> myOp = ">=";
> else
> myOp = "<";
>
> // and this is the clinker.....
> BuyCondition = ref(open, -x) myOp ref(close, -y) AND ref(close, -z)
myOp2 ref(close,-a) ...[ AND....AND ]
>
> You can see have a "variable operator" might keep it simple,
particularly where you might want to add further AND clauses to the buy
condition.
>
> Thanks again
>
> Robert Z
>
>
>
>
>
>
> ____________ _________ _________ __
> From: Mike sfclimb...@. ..
> To: amibro...@yahoogrou ps.com
> Sent: Thursday, 30 July, 2009 1:51:53 AM
> Subject: [amibroker] Re: Relational Operators assigned to variables?
>
>
> Just repeat the IIF within an IF:
>
> if (something) {
> x = iif ( Open > Close, 0, 1 );
> } else {
> x = iif ( Open < Close, 0, 1 );
> }
>
> Alternatively, get rid of the IIF entirely since the expression is
boolean (which returns 1 on true) and add a NOT operator to reverse it:
>
> if (something) {
> x = NOT (Open > Close);
> } else {
> x = NOT (Open < Close);
> }
>
> Getting rid of the NOT and reversing the logic gives:
>
> if (something) {
> x = (Open <= Close);
> } else {
> x = (Open >= Close);
> }
>
> If, on the other hand you want to keep the IIF, you could integrate
the 'something' into the IIF giving:
>
> x = iif(something, NOT (Open > Close), NOT (Open < Close));
>
> or:
>
> x = NOT iif(something, Open > Close, Open < Close);
>
> It all boils down to what is most 'readable' to you.
>
> Mike
>
> --- In amibro...@yahoogrou ps.com, "ics4mer" ics4mer@ > wrote:
> >
> > Hi all,
> >
> > A newbies question.
> >
> > Can I assign a relational operator to a variable?
> >
> > Logically, I'd like to do something like this:
> >
> > //// begin ex
> >
> > if ( something )
> > myRelOp = ">";
> > else
> > myRelOp = "<";
> >
> > iif ( Open myRelOp Close, 0, 1 );
> >
> > //// end ex
> >
> > I hope that makes sense!
> >
> > TIA
> >
> > Robert Z
> >
>
>
>
>
>
>
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