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Active Message Threads for March 2008
Andreas Wuestefeld
Hi again.
Athur Snoke just pointed out to me, that the ghostscrip package might be
of interest for some users (SGFTOPS...)
In the CYGWIN setup, it's located in
Grahics:
* ghostscript
Andy
No replies
Hi everybody
As of SAC version 101.1 the SAC development team made some adoptions to
ease installation under CYGWIN (http://www.cygwin.com/)
If you want to compile SAC under CYGWIN, you mainly need to have
installed several packages. Use the CYGWIN setup utility!
I list the necessary packages here by category (as of CYGWIN1.5):
=====================================================
1) Packages which *need* to be installed
Devel:
* gcc-g++
* libncurses-devel
* make
* readline
…
[more]
No replies
Rick Benson
Looking for superior quality repl1ca w4tches? Then welcome to the newly redesigned
Bell & R0ss, home of the best reproduction R0lex Sportm0del w4tches on the whole web!
Bell & R0ss 0ffers a tremendous selection of R0lex repl1ca timepieces for both
men and women, all of them featuring the original manuf4cturer markings along with a myriad
of details that make these w4tches look so much like the brand new R0lexes that
even the experts are having a hard time differentiating them!
http://www.Bell…
[more]
No replies
Onur Tan
Dear Xu
SAC uses omega convention. so you must multiply every poles and zeros
with 2*pi*f ( in general, f=1Hz for Guralp seismometers). Do not use
the values in Guralp Cal-Doc.
Add one Zero for integration.
And you have to calculate Constant using sensor and digitizer gain
values.
You can use this document:
http://www.le.ac.uk/seis-uk/downloads/seisuk_data_manage.pdf
I edit more detailed document, but in Turkish. If you want to read
only numbers :) in this document I can send you.
be…
[more]
No replies
Xuefeng Shang
Hi all,
I use command "transfer from EVALRESP to BBDISP" to deconvolve the
instrument response, and get error below:
Extracting evresp response for YKW1, BHE...
EVRESP ERROR (YKW1.CN..BHE [File: ./RESP.CN.YKW1..BHE; Start date:
1989,025,00:00:00; Stage: 4]):
check_channel; decimation blockette with no associated filter,
skipping to next response now
EVRESP ERROR (YKW1.CN..BHE [File: ./RESP.CN.YKW1..BHE; Start date:
1989,025,00:00:00; Stage: 4]):
check_channel; deci…
[more]
No replies
wwxu
Dear ALL,
I am using function "transfer" to deconvolve the instrument response in
SAC, the usage is as "transfer from polezero subtype cmg3esp.response to
none", and the file "cmg3esp.response" is in the format as SAC mannual
told(poles, zeros, constant), here I want to know what is the unit of poles
and zeros, radian/sec or Hz? it is very different as we know, can anyone
help me?
Your sincerely,
Xu W.
************************************************
Dr. WeiWei Xu
Institute of Geology and…
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No replies
sac-help@iris.washington.edu
(no body)
No replies
Sribharath Kainkaryam
(no body)
No replies
(no body)
No replies
Geo .
Greetings everyone,
I am in the process of writing a little macro to deconvolve the instrument
response using poles zeroes files. For this I have to set a blackboard
variable equal to the name of the poles zeros file for each instrument.
Example of such a file name is as follows,
SAC_PZs_US_JFWS_BHZ__1995.257.00.00.00.0000_2001.181.24.60.60.9999
I can set the first few characters of this file name using SETBB but the
probelm is "1995.257.00.00.00.0000_2001.181.24.60.60.9999" part. Does
anyone…
[more]
No replies
Robert Herrmann
sac-help-request@iris.washington.edu wrote:
The simple test of the FFT is to see the effect of an impulse:
fg impulse delta 0.1 npts 1024
w impulse.sac
*1. Test of sac2000 FFT
*Sac creates a time series with a centered impulse of height 1.0 and not
a unit area pulse.
fft
writesp am
This creates a series of the amplitude spectrum, which has values of
0.1, e.g., 1 (from the time series) * DT from the fft
ifft
This creates a time series consisting of a centered impulse with height 1.0
Th…
[more]
No replies
Hi, ALL
We suppose that x[n] and y[k] are a DFT pairs, i.e.
y[k]=1/N*sum_n(x[n]*exp(-2*pi*j*k*n/N)) n=0,1,...,N-1
where sum_n means the sum for n=0,1,N-1(similar for sum_k),
and dt is the sampling interval, df is the sampling frequency,
N is the sampling number.
To obey Parseval's theorem, we get
sum_n(x[n]*x[n])*dt=sum_k(y[k]*y[k])*df
since sum_n(x[n]*x[n])=N*sum_k(y[k]*y[k])
and df=1/(N*dt), also consider the amplitude symmetry of the real series,
we should multiply a coeffi…
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No replies
For an forward FFT (fft) in SAC the output series is scaled by the
time sampling or delta
For an inverse FFT (ifft) in SAC the output series is scaled by 1/
(delta * npts)
See below for a further discussion, but simply
fg sine 5 npts 1024 delta 0.01
# Put the delta back in
div 0.01
# Scale the FFT by the length of the signal
div 1024
fft
psp am
# Maximum should be around 0.5
writesp tmp
read tmp.am
lh depmax
# depmax should be about 4.671955e-01 (not exactly 0.5, but close)
Cheers
Brian…
[more]
No replies
derek
Hi Fiona,
I realize you are short of time, but perhaps these workarounds could be
helpful...
I don't know if this would be helpful, but (like a lot of folks), I have
a matlab m-file that reads in SAC time series files. Likewise there is
another that can write from Matlab to SAC. Perhaps this would be useful
in that you could read in the SAC files and then convert them to the
proper format for the surf. wave code to do it's stuff.
I also have matlab code to do multi-channel cross-correlati…
[more]
No replies
Fiona Darbyshire
2008-03-10 22:09:57
- 2008-03-10 22:58:44
Dear All,
I think I have identified the issues regarding the SAC input/output
associated with the cross-correlation program, but that has raised more
questions before I can actually solve the problem.
Some of the libraries called by the program are fairly standard ones that
appear in the regular "sacio.a" (and in Computer Programs in Seismology...)
- namely get*hv, set*hv, rsac*, wsac*. However, there are still 4
outstanding subroutine calls that are a problem.
I downloaded the most recent ve…
[more]
Replies
-
Re: SAC libraries - more detail & more complication - Robert Casey - 2008-03-10 19:47:34
-
Re: SAC libraries - more detail & more complication - Brian Savage - 2008-03-10 22:58:44
Tuna Eken
To message 3:
Hi Onur,
when I tried the same commands with the same parameters onto my example sac
file
it did worked out ... It actually gave the same error messae when i used
different time values (whis is not included by the data) ...
So problem may be caused by applying wrong values for your data. have you ever
checked starting end ending points of the data ?
regards
tuna eken
Message: 3
Date: Sat, 8 Mar 2008 13:29:51 +0200
From: "Onur Tan" <Onur.Tan@mam.gov.tr>
Subject: [SAC-HE…
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Replies
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Re: Re: sac-help Digest, Vol 33, Issue 4 - Brian Savage - 2008-03-10 16:44:51
Hi Tuna,
exactly, my data length is 1800 sec.
if you look the sample again, cutting limits is 600-700 sec.
the problem is the first variable ( %a )
when echo on, the second variable can not writen to the screen !
SAC> cut %a %b
cut %a %b
==> cut 600
Do you use the version 101.0?
I have no problem with old version.
onur
-----Original Message-----
From: sac-help-bounces@iris.washington.edu
[mailto:sac-help-bounces@iris.washington.edu] On Behalf Of Tuna Eken
Sent: Su…
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Replies
-
RE: Re: sac-help Digest, Vol 33, Issue 4 - Tuna Eken - 2008-03-09 20:31:55
Hi,
When I use a blackboard variable as the first parameter of the cut
command in SAC new version (101.0),
it gives error.
I tried this (echo on):
--------------------
SAC> setbb a 600
setbb a 600
SAC> setbb b 700
setbb b 700
SAC> cut %a %b
cut %a %b
==> cut 600
SAC> r
r
WARNING: Start cut greater than stop cut for file 08010_0707_CEV.1
ERROR 1301: No data files read in.
SAC>
-----------------------------
the cut command do not understand the second variable.
This does also not…
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No replies
Hi ALL,
In SAC, I generate a 5Hz sine wave and do fft transforming as follows:
sac> funcgen sine 5 npts 1024 delta 0.01
sac> fft
sac> psp am loglin
and I find that the maximum absolute amplitude is greater than 4 near
frequency 5Hz, but in theory, it should be 0.5 because of amplitude
spectrum symmetry of real series, so could you tell me why?
B.T.W., I also compute the amplitude spectrum using fft program I wrote and
find that the result is not the same with SAC generated, I checked the
pr…
[more]
No replies
Fiona Darbyshire
2008-03-08 02:13:09
Hello,
I have 2 SAC-related queries that are causing me problems on a couple of
fairly urgent projects currently:
i) I inherited a Matlab program for surface wave analysis. The seismogram
files that it reads are in PITSA ASCII format. Is there any existing
software to convert standard SAC to PITSA ASCII? Or will I have to convert
SAC binary to alpha, and try to reformat the resulting ascii files?
ii) Another inheritance: this time I have been given the source code
(fortran) for John VanDecar…
[more]
No replies
Sonia Castro Alarcon
Hi, I'm not sure if this is the email to write to find help but I didn't find other.
I'm trying to make a macro for ploting with the sgftops options. I use the command
sgftops f001.sgf file.eps 1 si
to set the options
*x translation :1
*y translation :1
*rotation angle:0
*scale...........:0.9
but I couldn't find the way to make the macro answer for this variables by itself and that makes I couldn't run it easy and in a loop for all the files.
Can you help me please?
thanks
Sonia Castro Alar…
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Replies
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Re: ploting with macros - Arthur Snoke - 2008-03-06 19:29:53
-
Re: ploting with macros - Xuzhang Shen - 2008-03-07 17:32:57
-
Re: ploting with macros - Brian Savage - 2008-03-07 16:39:09
-
Brian Savage
2008-03-05 23:33:22
Hersh,
The error you are seeing
> SAC> rbbf wndbbf_all
> ERROR 1203: Could not find VARS section
is because the blackboard files you are trying to read into SAC are
in a different byte order than
the machine you are on. The files can be swapped with a little
effort, but being able to read
blackboard variable files of either byte order should be available in
the next release of SAC.
Cheers,
Brian
On Mar 3, 2008, at 12:49 PM , Hersh Gilbert wrote:
> Hi SAC help,
>
> I am having tr…
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No replies
Thanks Rob, I don't have a Mac, so I guess I'll have to revert to
traditional rdseed,
On Fri, Feb 29, 2008 at 3:26 PM, <sac-help-request@iris.washington.edu>
wrote:
> Send sac-help mailing list submissions to
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>
> To subscribe or unsubscribe via the World Wide Web, visit
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