For that you need Fourier transform and FFT is coming as a built in function in 4.86
Best regards, Tomasz Janeczko amibroker.com ----- Original Message ----- From: "Fred" <[EMAIL PROTECTED]> To: <[email protected]> Sent: Friday, October 06, 2006 3:48 AM Subject: [amibroker] Re: Polynomial Trendlines > Now if someone can take this method and/or AFL or at least provide a > how to that takes us into Trigometric curve fitting and extrapolation > i.e. the solution of simultaneous equations in the generalized format > of a spectral model i.e. ... > > S ~ (a1 cos w1t + b1 sin w1t) + ... + (Am cos wm + bm sin wmt) > > Then we might have something fairly useful ... > > I suspect Gaussian Elimiation can be used for this as well, but I > don't have the skill level to calculate the necessary matrix entries > to get it down ... > > Any mathematicians out there ? > > > --- In [email protected], "Fred" <[EMAIL PROTECTED]> wrote: >> >> When stretch over enough data almost any order will become a pseudo >> straight line ... >> >> By their nature a first order IS a straight line, 2nd U shape, 3rd >> order sine wave etc ... >> >> Try highlighting a SMALLER segment of data by using the beginning > and >> ending range markers ... >> >> >> --- In [email protected], "d_hanegan" <dhanegan@> wrote: >> > >> > Fred: >> > >> > Thanks for your posts and all of the information concerning the >> > Polynomial Trendlines. When I run the code, I pretty much just > get >> > a straight green line; it does not fit my data. I thought I had >> > read all of the posts. Am I missing something? >> > >> > Thanks. >> > >> > Dan >> > --- In [email protected], "Fred" <ftonetti@> wrote: >> > > >> > > Be AWARE ... that was a hand picked image ... if you play with >> > > PolyFit you will see that sometimes data fits the > extrapolations, >> > > sometimes it doesn't. >> > > >> > > The higher the order, the flakier the extrapolations are likely >> to >> > > become ... >> > > >> > > So ... Remember what it is ... a generator of an equation in > the >> > form >> > > >> > > Y = a + bx + cx^2 + ... + nx^(n-1) >> > > >> > > Where the coeeficients were pick to fit the data. >> > > >> > > IMHO what PolyFit is, epecially with very high orders is a very >> > good >> > > detrender of IN SAMPLE data, nothing more, nothing less ... > That >> > in >> > > and of itself is a useful tool ... Gaussian Elimination can > also >> > be >> > > the basis for some other things that are pretty decent when the >> > order >> > > is kept fairly low i.e. 3 or 4 ... >> > > >> > > --- In [email protected], "Ara Kaloustian" <ara1@> > wrote: >> > > > >> > > > Polynomial TrendlinesFred, >> > > > >> > > > There have been a lot of posting on this subject. Your one >> > image >> > > however is a very powerful message of its potential. >> > > > >> > > > Now I have to go back and review all the post ... hoping to >> find >> > a >> > > good reference to study. >> > > > >> > > > Anyone using it succesfully now? >> > > > >> > > > Ara >> > > > ----- Original Message ----- >> > > > From: Fred Tonetti >> > > > To: [email protected] >> > > > Sent: Tuesday, October 03, 2006 3:32 PM >> > > > Subject: [amibroker] RE: Polynomial Trendlines >> > > > >> > > > >> > > > Oops . >> > > > >> > > > >> > > > >> > > > Meant to include this visual . >> > > > >> > > > >> > > > >> > > > Green is calculated . White is extrapolated . >> > > > >> > > > >> > > > >> > > > >> > > > >> > > > >> > > > >> > > > -------------------------------------------------------------- > -- >> - >> > --- >> > > ---------- >> > > > I am using the free version of SPAMfighter for private > users. >> > > > It has removed 8588 spam emails to date. >> > > > Paying users do not have this message in their emails. >> > > > Try SPAMfighter for free now! >> > > > >> > > >> > >> > > > > > > > Please note that this group is for discussion between users only. > > To get support from AmiBroker please send an e-mail directly to > SUPPORT {at} amibroker.com > > For other support material please check also: > http://www.amibroker.com/support.html > > > Yahoo! Groups Links > > > > > > > > > > > Please note that this group is for discussion between users only. To get support from AmiBroker please send an e-mail directly to SUPPORT {at} amibroker.com For other support material please check also: http://www.amibroker.com/support.html Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/amibroker/ <*> Your email settings: Individual Email | Traditional <*> To change settings online go to: http://groups.yahoo.com/group/amibroker/join (Yahoo! ID required) <*> To change settings via email: mailto:[EMAIL PROTECTED] mailto:[EMAIL PROTECTED] <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
