[amibroker] ValueWhen() function

["yps_trader" <yps_trader@xxxxxxxxx>]

Hello, 

my aim is to create an array with the closing price on the same day
of the year but one year ago. 
I figured I could use the ValueWhen function for this:

x=valuewhen(Dayofyear()==???,C,1);

However I am having problems with the expression. The expression 
should be true on every dayofyear() in the past with the same value
as the actual dayofyear().
The larger background is that I would like to create Seasonal Charts 
with Amibroker.
I wanted to do this, by averaging the Closing price of each specific 
dayofyear() of e.g. the last 10 years and then chart this array.

I hope someone can help me.

Regards  

dj





------------------------ Yahoo! Groups Sponsor --------------------~--> 
Make a clean sweep of pop-up ads. Yahoo! Companion Toolbar.
Now with Pop-Up Blocker. Get it for free!
http://us.click.yahoo.com/L5YrjA/eSIIAA/yQLSAA/GHeqlB/TM
--------------------------------------------------------------------~-> 

Check AmiBroker web page at:
http://www.amibroker.com/

Check group FAQ at: http://groups.yahoo.com/group/amibroker/files/groupfaq.html 
Yahoo! Groups Links

<*> To visit your group on the web, go to:
    http://groups.yahoo.com/group/amibroker/

<*> To unsubscribe from this group, send an email to:
    amibroker-unsubscribe@xxxxxxxxxxxxxxx

<*> Your use of Yahoo! Groups is subject to:
    http://docs.yahoo.com/info/terms/