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Welcome to the Bathymetry wiki!

Here is a work documentation to keep track of our progress:

1. Construction of Database (Organize the Data by Geological Information)

ssh -l class ers.ucsd.edu, cd cm_data/CM_data_git/new, ./login, \c sample, \d

You can run TABLE pings to see the data, or use ./look.sh to view some statistics about it.

Note that the source data we are using for the database are stored in /tmp/data folder. Currently only a small portion of data is loaded in the table, as we are still in the experimenting phase so there is no need to get access to the whole dataset. However, if we are successful in running the data editing process, we might be able to build the complete database.

2. Fledermaus Software (Visualization Software for Human Editing data on the map)

Here are some reference that we found might help the understanding of this software.

https://confluence.qps.nl/display/FM770/Fledermaus https://cloudstor.aarnet.edu.au/plus/index.php/s/Ql4mgZeYqzvbjDt#pdfviewer

Fledermaus is located at /Applications/QPS/Fledermaus folder.

1. Data Preprocessing

To load a cm_file directly in Fledermaus for visual display and edit, we can simply run the following commands:

$ awk '{print($2,$3,$4)}' < 19170010.cm > test.xyz

awk command is a powerful command which can manipulate the text files efficiently. Here we output some specific rows (long, lat, depth) into a new file called test.xyz

$gmt minmax test.xyz// gmt is the Generic Mapping Tools for manipulating geographic and Cartesian data sets (including filtering, trend fitting, gridding, projecting, etc.)

http://gmt.soest.hawaii.edu/doc/latest/grdcut.html

$gmt grdcut topo30.grd -R34/61/12/28 -Gtest.grd=ef // This is the line where we cut the topo30.grd into a new grid map called Gtest.grd, at locations 34E - 61E, 12N - 28N.

// or using this gmt grdcut topo30.grd -R34/61/12/28 -fg -Gtest.grd=cf

After doing this, you can display the existing gridded map along with the xyz data collected from cruise at the same time on Fledermaus, and do some comparisons on the measured depth to identify bad points.

2. Importing Data

Upon opening Fledermaus, Import -> gridded data -> test.grd Import -> Points -> test.xyz Select Mode-> choose data point(s) on map -> Export -> output.xyz