SAC Help

A forum for SAC users to exchange ideas and ask questions about SAC usage, installation, portability, etc.

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Active Message Threads for December 2006

2006-12-15 13:57:40
Hi first, i would like to deeply thanks all people helped me in the past and give their experince and notes about my questions. here, i would like to perform a vector summ of the 2 component EW and NS after FFT. for a set of files (say 90). in this form of formula: sqrt((EW)**2+(NS)**2) how do i do this operation in sac using a macro..? for your note, the EW & NS component in the equation is a file name which is contain the spectral data for each components. … [more]
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Jim Lawson
2006-12-12 02:25:47
Does anyone have a SAC macro to estimate azimuth (and perhaps apparent velocity) from 3C grams from well matched seismometers? I know that Z could be estimated by using trial and error with "rotate". The same can be done perhaps more easily in Seis2K. At one time we obtained surprisingly good azimuths (and almost useless apparent velocities) with Geotool. but we lost our copy, and apparently only the NDCs are now allowed to have geotool. Jim Lawson Oklahoma Geological Survey, Leonard
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Geo .
2006-12-11 17:52:07
Greetings all, I was wondering if anyone knows how I could completely re-do the time axis may be by changing the header? Say I cut a window and want to assign 0 to starting point so that I can have the same time scale for all the cut seismograms ? e.g. I cut a window between 250-300 s in seismogram A and a window between 300-350s in seismogram B. Now I want to have the same time scale for A & B so that both A, B will have the time scale as 0-50s so that I can align the seismograms? Thanks ! J… [more]
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2006-12-05 19:43:37
Hello, Fellow-SAC'ers, I haven't gotten a response to my question (included below), so thought I would try again. I'll rephrase the original question and add to it. I am plotting XY data in a text (ascii) file using readtable (readtable content Y). The x-value is time (julian day). Readtable seems to have no means for interpolating missing values (using a sample rate, which would have to be supplied somewhere) and plotting a zero for any values that don't exist in the data file (as in th… [more]
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Geo .
2006-12-05 03:57:08
Thanks Eva ! will try that and see.... Januka. On 12/4/06, <> wrote: > > Send sac-help mailing list submissions to > > > To subscribe or unsubscribe via the World Wide Web, visit > > or, via email, send a message with subject or body 'help' to > > > You can reach the person man… [more]
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Hi their i was trying to use plot command to plot sac file for picking. but, actually, i don't know what is going on. when i tried the plot command it seems work for me fine. but, later on its won't work good with error message. and same message appear all the time when i use various plot command like Plot1, plot2....and Plotpk...!! its never plot anything with error message...!! terminal log file: ---------------------------------------------------------------------------… [more]
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Eva-Maria Rumpfhuber
2006-12-04 00:16:27
Hey Januka, I usually use a csh-script to sort data, and use sac just to extract the header information. You can try something like this, the following script will extract you the header information and store it in a file I called "rayp.list". Let me know, if it doesn't work. Good luck, eva #/bin/csh # This is a script to extract header information from a # sac file. # Selects all seismograms sorted by events # (you need to change print $2 to what works for you) set event = ` ls *.sac | na… [more]
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Geo .
2006-12-03 06:41:04
Greetings, I am interested in seperating a bunch of seismograms according to different GCARC values, for example, bunch up all the seismograms that are between 100 & 120 together ... so on and so forth. Is it possible to do this in SAC? any clues? Thank you. Januka.
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2006-12-02 21:53:24
Dear SAC Users and Developers does anybody knows where i can find read_dhi? which downloads waveforms through sac? Thanks Apo.
Geo .
2006-12-01 07:30:04
Hi Andreas, Thanks, ha ha yes, I didn't expect my old text to grow that long ! Januka. On 11/30/06, <> wrote: > > Send sac-help mailing list submissions to > > > To subscribe or unsubscribe via the World Wide Web, visit > > or, via email, send a message with subject or body 'help' to > sac-help-request@iris.washing… [more]
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