From: Hans-Bernhard B. <br...@ph...> - 2004-06-03 15:46:45
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On Sat, 8 May 2004, Vijayaraj AK wrote: > I was using GNU for plotting function and I wanted to > plot time in hour:min:sec:millisecond format. I > searched extensively for this kind of format. If this > is not defined it would be incredibly useful to have > such a format in future release. I suspect it's nowhere near as useful as you think it is. It's practically impossible to actually need both millisecond resolution and an entire hour of reach on a single axis --- no output device you're likely to use will be able to resolve 3 million positions along a single axis. -- Hans-Bernhard Broeker (br...@ph...) Even if all the snow were burnt, ashes would remain. |
From: Hans-Bernhard B. <br...@ph...> - 2004-06-03 16:05:33
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On Thu, 3 Jun 2004, Vijayaraj AK wrote: > Well, the data need not be generated every > millisecond. And yeah as you point out, it is not > logged for hours. I want to plot lets say, 20-30min > duration log of data sampled at 20-30ms interval. Well, that's still an axis range of 20*60/0.02 = 60000 samples. Do you have an output device with sixty thousand pixels along the axis? I doubt it. So I'ld suggest you just use extended 'using' specs and a format string for this: plot 'datafile' u ($1*3600+$2*60+$3):4 '%lf:%lf:%lf %lf' It might even work ;-) -- Hans-Bernhard Broeker (br...@ph...) Even if all the snow were burnt, ashes would remain. |
From: Vijayaraj AK <vij...@ya...> - 2004-06-03 15:53:18
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Well, the data need not be generated every millisecond. And yeah as you point out, it is not logged for hours. I want to plot lets say, 20-30min duration log of data sampled at 20-30ms interval. To make the plot look good and ease of reference, hour is also logged and displayed, though it might not be useful. As for the usefulness, I work for Qualcomm and we collect extensive amount of data and they are all in milli-second granularity. As for now, I just convert the timestamp into a number "seconds.milliseconds" and plot data vs xxx.000 number. It serves my purpose. It would just make plotting easier if a format was created that takes care of this. Thanks for you attention! Vijay. --- Hans-Bernhard Broeker <br...@ph...> wrote: > On Sat, 8 May 2004, Vijayaraj AK wrote: > > > I was using GNU for plotting function and I wanted > to > > plot time in hour:min:sec:millisecond format. I > > searched extensively for this kind of format. If > this > > is not defined it would be incredibly useful to > have > > such a format in future release. > > I suspect it's nowhere near as useful as you think > it is. It's > practically impossible to actually need both > millisecond resolution and an > entire hour of reach on a single axis --- no output > device you're likely > to use will be able to resolve 3 million positions > along a single axis. > > -- > Hans-Bernhard Broeker > (br...@ph...) > Even if all the snow were burnt, ashes would remain. > > ===== Vijayaraj A.K. #304, Creekside Apartments, \\\|/// o00o 505, 27th WAY, \\ - - // ( ) Boulder, CO 80305, ( 0 0 ) ( ) USA ***oOOo--(_)--******* Phone : (R) 303 499 1818 (O) 303 247 5061 Hello!! __________________________________ Do you Yahoo!? Friends. Fun. Try the all-new Yahoo! Messenger. http://messenger.yahoo.com/ |
From: Daniel J S. <dan...@ie...> - 2004-06-03 16:55:12
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Vijayaraj AK wrote: >Well, the data need not be generated every >millisecond. And yeah as you point out, it is not >logged for hours. I want to plot lets say, 20-30min >duration log of data sampled at 20-30ms interval. > > Oh, well that is not so much ms resolution. If you are displaying 20-30 min at 20-30 ms sampling rate, that's 60,000 data points, quite a lot of data for one plot. In other words, it doesn't match the resolution of the plotting device. That is, if there is some event on the scale of 20-100 ms, it may be the case that gnuplot will detect it because a min/max strategy is used. But in terms of a display of 20-30 min, you wouldn't be able to tell if that was a 100 ms event or a 10 s event. Some form of preprocessing and downsampling might be in order, although perhaps not essential. My interpretation of a generalized time format might be year:month:day:hour:min:second:millisecond with an option for indicating what units the data is in, i.e., year, day, hour, etc. And then the scale would adjust to display the appropriate units. However, that's a lot of work. Dan |
From: Daniel J S. <dan...@ie...> - 2004-06-03 16:19:46
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Hans-Bernhard Broeker wrote: >On Sat, 8 May 2004, Vijayaraj AK wrote: > > > >>I was using GNU for plotting function and I wanted to >>plot time in hour:min:sec:millisecond format. I >>searched extensively for this kind of format. If this >>is not defined it would be incredibly useful to have >>such a format in future release. >> >> > >I suspect it's nowhere near as useful as you think it is. It's >practically impossible to actually need both millisecond resolution and an >entire hour of reach on a single axis --- no output device you're likely >to use will be able to resolve 3 million positions along a single axis. > I'm guessing Vijayaraj basically meant that he wants millisecond resolution. (Even still, if not I'm guessing there are a lot of applications that may be synchronized to a clock and watch for short transient events and time-stamp the event. Hence, may want the hour/min/sec information along for the ride.) In any case, if millisecond resolution is desired, this is a base 10 unit (as opposed to "base 60"). Normal plotting should suffice so long as you don't go across a one minute boundary. Dan |