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      FLEXWIN - AUTOMATED TIME-WINDOW SELECTION ALGORITHM
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Alessia Maggi
[email protected]

Welcome to the flexwin package.  The purpose of this package is to
select windows on pairs of observed and synthetic seismograms on which
measurements can subsequently be made.

This is a bare-bones instruction set.  For more details read the flexwin manual
(flexwin_manual.pdf) and the flexwin article (Maggi et al, GJI, 2009).

If you have suggestions for fixes or future updates, please send me an email.
I will post them in the file FUTURE_UPDATES.

THE PACKAGE
-----------

The package contains the flexwin code and documentation, as well as a set of
test data, examples of user files for different scenarios, and a set of utility
scripts that may be useful for running flexwin on large datasets.

QUICK TEST
-------------

For quick start-to-finish testing with the sample data set provided,
execute these commands from within the base directory:

cd ttimes_mod
make -f make_gfortran
make -f make_gfortran install
cd ..
make -f make_gfortran
make -f make_gfortran test

NOTE 1: the last command will run flexwin in test_data/ and also plot
NOTE 2: to clean: make clean -f make_gfortran 

If all goes well, it should pick 7 time windows:
 Selected windows, start and end time, CC, Tshift, dlnA  
   1   1054.600  1484.600     0.957    -3.000     0.073
   2   1719.600  2067.600     0.973     0.000     0.172
   3   2067.600  2457.600     0.965    -5.000    -0.171
   4   2457.600  2672.600     0.982    -5.000     0.184
   5   2851.600  3108.600     0.969    -6.000     0.091
   6   3108.600  3407.600     0.893     4.000    -0.130
   7   3502.600  3937.600     0.833    -9.000    -0.636
 DEBUG : writing output seismos

You should see the file MEASURE/ABKT.II.LHZ.seis.ps,
which should have several time series as well as seven windows.
Compare output files with those in MEASURE.orig/, described below.
Note that the plotting script requires GMT (http://gmt.soest.hawaii.edu/).

Last tested 15-Aug-2012 with the following:
  linux: 64-bit, opensuse 12.1
  sac 101.5
  gfortran 4.6.2
  GMT 4.5.3 (for plotting)

COMPILATION
-----------

FLEXWIN requires the following libraries external to the package in order to
compile and run: libsacio.a and libsac.a. Both libraries
are distributed by IRIS as part of the SAC package (version 101.2 and above).
The IRIS download site (as of 10-Nov-2010) is here:
   http://www.iris.edu/forms/sac_request.htm
(To check your version, type sac.)

If your compiler of choice is gfortran, then you should be able to use the
make_gfortran makefiles with only minor modifications (notably you may need to
change the search path for the libsacio.a library).  If you prefer another
compiler, you should modify the OPT and FC lines in the makefiles accordingly.
The makefile requires GNU make.

IMPORTANT NOTE: The default setting assume a 64-bit operating system,
compatible with SAC 101.3b (August 2009) and higher.
For older SAC versions, you must have the -m32 option, which makes
32bit binaries.  In particular
  OPT=-m32 -Wall         -- make_gfortran
  OPT=-m32               -- ttimes_mod/make_gfortran

Steps to compile the flexwin package:

(1) Compile libtau.a and create iasp91.hed and iasp91.tbl.  In the
flexwin/ttimes_mod directory type: "make -f make_gfortran".  This will compile
libtau.a, and two programs, remodl and setbrn.  The makefile will also run
remodl and setbrn to create the iasp91.hed and iasp91.tbl files.  You should
then type "make -f make_gfortran install" to install the iasp91 files.

(2) Compile flexwin.  Edit the make_gfortran file in the flexwin root directory to ensure the SACLIBDIR variable points to the location of your SAC libraries (by default $SACHOME/lib).  Then type "make -f make_gfortran".

You should end up with the flexwin executable.  The program requires the iasp91
files (or links to them) to be present in the directory from which the code is
launched. 


TEST DATA SET
-------------

You should test your compiled code on the test_data dataset provided.
In the flexwin/test_data directory, type "./flexwin < input.test".
The results of your run will be found in the MEASURE subdirectory,
and should match those found in the MEASURE.orig subdirectory.

You can also test the basic plotting script by running "./plot_seismos_gmt.sh
MEASURE/ABKT.II.LHZ", whose output will be MEASURE/ABKT.II.LHZ.seis.eps.
Note that plotting scripts require GMT.


RUNNING FLEXWIN
---------------
In general, flexwin is run as follows:

./flexwin < input

where the "input" file is formatted as follows:

327
RAW_DATA/9627721.CI.ADO.BHR.sac.d.fil
SYNTH/ADO.CI.BHR.new.fil
MEASURE/ADO.CI.BHR
RAW_DATA/9627721.CI.ADO.BHT.sac.d.fil
SYNTH/ADO.CI.BHT.new.fil
MEASURE/ADO.CI.BHT
RAW_DATA/9627721.CI.ADO.BHZ.sac.d.fil
SYNTH/ADO.CI.BHZ.new.fil
MEASURE/ADO.CI.BHZ
....

i.e. the number of traces to be measured, followed by (in order) the path to
the raw data sac file, the path to the synthetic sac file and the path and
basename for the (many!) output files for that trace.  



OUTPUT FILES
-----------

Most output files are in ascii.  All file names start with the basename given
in the input file for that trace:

basename.obs		= ascii observed seismogram (filtered) 
basename.syn		= ascii synthetic seismogram (filtered)
basename.obs_lp.sac = sac observed seismogram (filtered)
basename.syn_lp.sac = sac synthetic seismogram (filtered)
basename.env.obs	= ascii envelope of observed seismogram (filtered)
basename.env.syn	= ascii envelope of synthetic seismogram (filtered)
basename.win		= list of windows with theoretical phase arrival times
basename.win.qual	= list of windows with Tshift,CC,dlnA values 
basename.phases		= theoretical arrival times of phases
basename.stalta		= STA:LTA timeseries used to select the windows, 
                    and the time-dependent values of the STA:LTA water 
                    level, the CC limit, the Tshift limit, the dlnA 
                    limit and the window signal to noise limit.
basename.info		= information on the path and some statistics

For more details about the file formats, your best bet is to read the write_
subroutines in io_subs.f90.



SCRIPTS
-------

Several plotting routines (plot_*.sh) are provided as examples for
plotting seismograms, measurements and adjoint sources.  All plotting is
done in gmt.  These scripts will need to be modified to suit your
particular plotting needs.

The script extract_event_windowing_stats.sh extracts statistical
information on the window selection process, on the measurements.  Again,
you can use use this script as a template for your own information
extraction needs.



CONFIGURING FLEXWIN FOR YOUR SCENARIO
-------------------------------------

After having read the flexwin article to learn how
flexwin works, you should refer to the flexwin manual
(flexwin_manual.pdf) for basic configuration instructions.