PARTICLEREDDY wrote:> ok andor, > before saying it as a funny question, try to put your > brain into new technologies then you will know, where exactly this > question has arised. i am sorry, but your idiotic answer is provoking > me to say this..have brain and think and then only answer.. > > and further behave has an engineering professional before giving > USELESS and WORTHLESS ANSWERS.Your frustration is evident, but it doesn't justify rudeness. Your question as stated is, if not funny, decidedly peculiar. Two possibilities come to mind: either you just don't know what you're asking about, or you're expressing yourself very poorly. I've been trying to elicit the meat of the matter from you, but your rudeness put me off. I'll await your apology before communicating with you again. Jerry -- Engineering is the art of making what you want from things you can get. �����������������������������������������������������������������������
FFT SIZE DETECTION
Started by ●July 17, 2006
Reply by ●July 17, 20062006-07-17
Reply by ●July 17, 20062006-07-17
"PARTICLEREDDY" <particlereddy@gmail.com> writes:> ok andor, > before saying it as a funny question, try to put your > brain into new technologies then you will know, where exactly this > question has arised. i am sorry, but your idiotic answer is provoking > me to say this..have brain and think and then only answer.. > > and further behave has an engineering professional before giving > USELESS and WORTHLESS ANSWERS. > > particlereddyParticle, Why don't you simply let people know a bit more about what you are trying to do and what your new technologies are? Do you work for the secret service? As long as you cannot explain why you work with data and the only thing you know is that it is "fft data", your quesion is just funny. Do you know what number format is used? 32bit or 64bit floats, fixpoint? Do you know if the input data to the ffts was real or complex? Do you know the order of the fft data? Do you know if the frames overlap? Do you know if the size should be a power of 2? If you let everybody in the dark, nobody can give you a USEFULL or VALUABLE ANSWER. Anton
Reply by ●July 17, 20062006-07-17
Paul Russell wrote:> > jim wrote: > > > Somebody else already mentioned symmetry. That seems like your only > > hope. > > > > I suppose if it were a stream of FFTs then you could look for > periodicity (assuming that successive FFTs were reasonably correlated).Yes, if it were known that the data was serial and that the FFT's were all the same size it would make the problem simpler. -jim ----== Posted via Newsfeeds.Com - Unlimited-Unrestricted-Secure Usenet News==---- http://www.newsfeeds.com The #1 Newsgroup Service in the World! 120,000+ Newsgroups ----= East and West-Coast Server Farms - Total Privacy via Encryption =----
Reply by ●July 17, 20062006-07-17
"PARTICLEREDDY" <particlereddy@gmail.com> wrote in message news:1153139630.763945.14790@m73g2000cwd.googlegroups.com... The question is interesting because you don't tell us: - what you're looking at (so we have to assume that it's a sequence of numbers) - what you're looking at is presumably real time data? - the size of the arrays of these numbers (but your assertion implies that there are no blocks; rather that the data comes sequentially and continuously without frames being identified) It that it? IF that's the case then the suggestion to seek periodicities is probably a good one. This assumes that portions of the FFT will repeat from frame to frame. Autocorrelation comes to mind. Fred
Reply by ●July 17, 20062006-07-17
Fred Marshall wrote:> "PARTICLEREDDY" <particlereddy@gmail.com> wrote in message > news:1153139630.763945.14790@m73g2000cwd.googlegroups.com... > > The question is interesting because you don't tell us: > - what you're looking at (so we have to assume that it's a sequence of > numbers) > - what you're looking at is presumably real time data? > - the size of the arrays of these numbers (but your assertion implies that > there are no blocks; rather that the data comes sequentially and > continuously without frames being identified) > It that it? > > > IF that's the case then the suggestion to seek periodicities is probably a > good one. This assumes that portions of the FFT will repeat from frame to > frame. Autocorrelation comes to mind.Fred, I'd like to see us all wait for an apology to Andor before offering any further suggestions. "ok andor, before saying it as a funny question, try to put your brain into new technologies then you will know, where exactly this question has arised. i am sorry, but your idiotic answer is provoking me to say this..have brain and think and then only answer.. and further behave has an engineering professional before giving USELESS and WORTHLESS ANSWERS." is out of bounds for polite discourse. Jerry -- Engineering is the art of making what you want from things you can get. �����������������������������������������������������������������������
Reply by ●July 18, 20062006-07-18
hi jerry and andor,
seems everyone has trained guns against
me.doesnt matter. for first and last no apologies to anyone.
problem stated here;
X(n) ---- > complex random signal.
W(n) ------ > Noise vector.
Y(n) = X(n) + W(n). (obviously Y(n) is complex vector)
assume that Y(n) is of 10000 samples length.
i will be taking fft of Y(n) in chunks of (choice --- >128, 256 and
512), now i have the FFT of the Y(n).
1. I Dont know what is the length of the FFT TAKEN.
2. I DONT KNOW WHAT IS THE LENGTH OF THE SIGNAL TAKEN.
now dear all,
i have to find out size of the fft taken on the
signal ???
any more clarifications please do ask
ANY FURTHER AGAIN NO APOLOGIES..i didnt do any mistake. if people
presume my behaviour as rude, its their mistake.
particlereddy
Reply by ●July 18, 20062006-07-18
hi jerry and andor,
seems everyone has trained guns against
me.doesnt matter. for first and last no apologies to anyone.
problem stated here;
X(n) ---- > complex random signal.
W(n) ------ > Noise vector.
Y(n) = X(n) + W(n). (obviously Y(n) is complex vector)
assume that Y(n) is of 10000 samples length.
i will be taking fft of Y(n) in chunks of (choice --- >128, 256 and
512), now i have the FFT of the Y(n).
1. I Dont know what is the length of the FFT TAKEN.
2. I DONT KNOW WHAT IS THE LENGTH OF THE SIGNAL TAKEN.
now dear all,
i have to find out size of the fft taken on the
signal ???
any more clarifications please do ask
ANY FURTHER AGAIN NO APOLOGIES..i didnt do any mistake. if people
presume my behaviour as rude, its their mistake.
particlereddy
Reply by ●July 18, 20062006-07-18
Hi Par, On Mon, 17 Jul 2006 21:26:59 -0700, PARTICLEREDDY wrote:> seems everyone has trained guns against > me.doesnt matter. for first and last no apologies to anyone.Don't sweat it. It's too hard to infer tone of voice or attitude on Usenet, so it's best not to infer either. It didn't seem to me that anyone here had guns trained. They just didn't understand your question. Since most of the regulars here have been DSP professionals and/or professors for a very, very long time, that might indicate something to you about the way you phrased your question...> problem stated here; > > X(n) ---- > complex random signal. > > W(n) ------ > Noise vector. > > Y(n) = X(n) + W(n). (obviously Y(n) is complex vector) > > assume that Y(n) is of 10000 samples length. > > i will be taking fft of Y(n) in chunks of (choice --- >128, 256 and > 512), now i have the FFT of the Y(n).How is this statement compatible with question one? Doesn't the fact that you've taken the FFT indicate that you know how long it is?> 1. I Dont know what is the length of the FFT TAKEN.Maybe "taken" means something special when shouted?> 2. I DONT KNOW WHAT IS THE LENGTH OF THE SIGNAL TAKEN.Didn't you just say that it was 10000 samples? Maybe this question has special meaning because it's been shouted, too.> i have to find out size of the fft taken on the > signal ???You seem to have done the taking. How can you not know?> any more clarifications please do askJust the questions above.> ANY FURTHER AGAIN NO APOLOGIES..i didnt do any mistake. if people > presume my behaviour as rude, its their mistake.Sure. Just remember that replying to questions on comp.dsp is a recreation. How participants react to you is naturally up to them. Cheers, -- Andrew
Reply by ●July 18, 20062006-07-18
PARTICLEREDDY wrote:> > hi jerry and andor, > seems everyone has trained guns against > me.doesnt matter. for first and last no apologies to anyone.Well, I for one agree. You have nothing to apologize about. The discourse so far has gone something like this: You state the problem (politely I noted). Others respond telling you the problem is stated badly. You respond saying 'No it is not stated badly and adding that their response is useless and worthless'. In turn they respond telling you in so many words that your response is useless and worthless. Someone mentions you should apologize. So it looks like both sides are just going to continue calling the others response useless and worthless. And I don't see how apologies from either side will be changing that. So lets start from the assumption that your problem statement is not useless and worthless as others are claiming. That leads one to the conclusion that between the time that your original Y(n) is processed and the "FFT taken" and the present time the information required to take the FFT in the first place is somehow lost. Thus the task you are asking about is how to recover that lost information. One question: Do you have any way of knowing whether the FFT frames are stored sequentially in chronological order and whether all of the FFT frames are of the same size? -jim> > problem stated here; > > X(n) ---- > complex random signal. > > W(n) ------ > Noise vector. > > Y(n) = X(n) + W(n). (obviously Y(n) is complex vector) > > assume that Y(n) is of 10000 samples length. > > i will be taking fft of Y(n) in chunks of (choice --- >128, 256 and > 512), now i have the FFT of the Y(n). > > 1. I Dont know what is the length of the FFT TAKEN. > > 2. I DONT KNOW WHAT IS THE LENGTH OF THE SIGNAL TAKEN. > > now dear all, > i have to find out size of the fft taken on the > signal ??? > > any more clarifications please do ask > > ANY FURTHER AGAIN NO APOLOGIES..i didnt do any mistake. if people > presume my behaviour as rude, its their mistake. > > particlereddy----== Posted via Newsfeeds.Com - Unlimited-Unrestricted-Secure Usenet News==---- http://www.newsfeeds.com The #1 Newsgroup Service in the World! 120,000+ Newsgroups ----= East and West-Coast Server Farms - Total Privacy via Encryption =----
Reply by ●July 18, 20062006-07-18
>ok andor, > before saying it as a funny question, try to put your >brain into new technologies then you will know, where exactly this >question has arised.Hallo Particle:-) What is "put your brain"??? What are those new technologies? I am very much interested to know about it. i am sorry, but your idiotic answer is provoking>me to say this..have brain and think and then only answer.. > >and further behave has an engineering professional before giving >USELESS and WORTHLESS ANSWERS.Are you an engineering professional? -San>particlereddy > >
