If you guys see my post under 'AFL 101' a couple of days back I was saying that the one thing that would have really helped me as a newbie was a chapter of the user manual outlining the AmiBroker execution cycle... I think a lack of understanding of that execution cycle is what's confusing you guys right now...
Conrad I find your description of what you are seeing very confusing. Can you post the code here and I'm sure you'll get some feedback from those of us who have worked a few things out with AB. --- In [email protected], Snoopy <snoopy.p...@...> wrote: > > Conrad, > > I am a newbie as well, so I might be way off base, and expect more > experienced folks to set us straight... > > I think you (and I) have not fully grasped the ARRAY Processing > methodology of AFL. > > Try thinking of it as if you are using Excel - and you paste a formula > into an entire ROW. > When you finish the paste, it does the calculation. > > You (and I) need to better understand what triggers the running of the > AFL (I assume a new data bar will trigger it - not sure when - start, or > complete). > > And for your benefit, you could also use the afl functions for First > Visible Bar and Last Visible Bar. > > I hope this helps. > > Snoopy > > Conrad Joach wrote: > > > > I'm just not understanding the way AB is evaluating AFL for a chart. > > Let me break it down. > > > > Let's say I have a database with 100 1 minute bars, 100 minutes of quotes. > > > > Now let's say I have a chart, and that chart is very narrow and only > > shows 10 bars worth of data. > > > > I write an AFL sript. I want to do a very simple thing. > > > > For every bar in the series of 100, I want to check if it's visible > > (meaning it's inside the 10 bar window that is viewable in the chart), > > I want to print the date and time of that bar. For this example let's > > say the chart is positioned at the end, showing bar 91-100. > > > > The script should send the date and time of bars 91-100 to the trace > > window. As far as I'm concerned there should only be *10* lines in the > > trace window, no more, no less. I guess this means setting the forward > > bar padding to 0, and the prior bars to 0. > > > > But here's the catch. These 100 bars are history. As soon as its > > loaded, bar 101 comes in across the wire. The script should only run > > *once* for bar 101. > > > > This is the paradigm I'm used to seeing in almost every other > > backtesting system. I don't want my AFL script to run 10 times for > > bars 92-101 when that 101st bar crosses the wire. I just want the last > > bar evaluated, and the ability to look back at prior bars. > > > > Where am I going wrong? Many thanks for any help you can provide. > > > > >
