rflexa is a complete receiver function workflow tool, with the purpose of assisting the observational seismologist from station to subsurface. Although initially built for receiver function analysis, the individual modules can be extracted for use and integrated into your existing workflow. rflexa exists as two independent branches, a MATLAB version, and a Python version.
This guide is not intended to be a complete introduction to Python, but if you are new to the Python programming language I highly recommend you go through the following steps before continuing any further with rflexa:
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Install the Anaconda package manager.
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Depending on how you prefer to write code, do one of the following:
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If you like to work from the command-line/terminal, read about setting up conda to work from the command-line.
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If you like to work within an IDE, search Google for a tutorial on how to setup conda in your respective IDE. I recommend PyCharm, as it is built entirely for Python development and comes with a thorough conda setup guide. The Community version is free and has been sufficient for my needs.
rflexa is built on top of the ObsPy package, and requires that you have ObsPy installed in order to run properly. If you already have ObsPy installed, you can continue to the download and use the source code from the folders above.
For a thorough explanation of the functions included in the MATLAB version of rflexa, consult the documentation here.
The TauP Toolkit is a useful command line utility which allows you to quickly calculate theoretical travel times for a wide variety of seismic phases. To begin installing it, go to the TauP Website and download the latest release (as of this writing, TauP-2.4.5).
If you have experience with the command line (also known as the Terminal), then you'll most likely be able to complete the installation by following Section A of the official TauP documentation. If you're not very comfortable with the command line, then continue reading!
If you haven't already done so, download the latest version of the TauP Toolkit and save it to your ~/Downloads folder.
Once the Terminal successfully launches, execute the following command to navigate to your ~/Downloads folder:
cd ~/Downloadsyou will make frequent use of the Terminal as a seismologist, so it's best if you start
getting familiar with it now! The cd command means change directory. In Unix world,
a folder is referred to as a directory, so this command is equivalent to opening up
Finder and clicking on your Downloads folder.
Now that we are in the ~/Downloads folder, go ahead and run the following command in the Terminal:
gunzip TauP*if this fails for some reason, try running the following commands, one at a time, until one works:
tar -xvf TauP*
unzip TauP*You should now have a new folder in your ~/Downloads folder called TauP-X.X.X where X refers to
the version number. Before we contine, lets unpack the commands we just executed a bit.
The commands gunzip, tar -xvf, and unzip all have the effect of taking a .tar or .zip file and
inflating them. When you are sharing a large piece of software, or any large folder, it is good practice
to compress the folder so that the file size isn't quite as large. Your installation of the TauP Toolkit
came as a compressed file, so we needed to decompress it by running the above command.
The second part of our command, referred to as the argument, was TauP*. The * in this command is known
as a wildcard. This means that, after executing our command, the computer checks to see if there are any files
that start with TauP in the current directory. If it finds a match, it executes the command on this file, and
then proceeds to check if there are any more files that match. If, for example, you had downloaded 5 copies of
the TauP Toolkit, this command would effectively decompress all 5 of them.
Next, we are going to move the TauP folder somewhere where we can easily find and access it. Since some of you may be working on computers without root access, we will put it in our home directory. You can do this by executing:
mv TauP* ~/to check that this was successful, execute:
cd ~/followed by:
lswhich lists all of the files and folders in the current directory. The first command, mv, had the effect
of moving the TauP folder to the home directory ~/. The second then took us from the ~/Downloads folder to
our home directory, which is universally referred to as ~/. Before moving forward, make sure the ls command
showed the TauP folder.
Now, we need to add TauP to our $PATH variable. You can do this by opening your ~/.bash_profile file
using a command line editor such as emacs. If you have emacs
up and running, the following will open your ~/.bash_profile file:
emacs -nw ~/.bash_profileonce the file opens, add the following lines to the bottom:
# Added for the TauP Toolkit
export TAUPHOME=/Users/$USERNAME/Taup-X.X.X
export PATH=$TAUPHOME/bin:$PATHwhere you replace $USERNAME by your username, which you can find by typing pwd in your home directory, and Taup-X.X.X with the version of TauP that you downloaded. These commands are creating a new environment variable named
TAUPHOME, and adding it to your $PATH. In Unix, your $PATH is a set of directories which your command line
can access from anywhere, so files in those directories, like the TauP executables, can be executed from anywhere.
The last step before we can run the TauP Toolkit is applying the changes we just made to our ~/.bash_profile
file by sourcing it with the following:
source ~/.bash_profileAfter doing this, verify that everything has worked by executing:
taup_timeif everything was successful, an interactive input should appear asking you to specify model parameters for a travel time calculation. Congratulations! You now have a useful command line utility ready to invoke at a moment's notice.