Geokerr Code

This is the website for the code Geokerr presented in Dexter & Agol (ApJ, 696, 1616). If you use these routines in your research, please cite this paper. If you find any bugs in these routines, please let me know and I will make my best effort to correct them.

The 5/18/2009 release includes an option for concentrating resolution near radial turning points, which was lacking previously. It also contains a couple of bug fixes. Thanks to those who reported bugs, and please let us know when you encounter issues with the current version.

Includes geokerr.f which contains the source code written in FORTRAN77, which is an example of an appropriate input file, inputex.f which contains FORTRAN source for writing a custom input file, and the user manual geokerr_readme.

To get started quickly, uncompress the package using

tar -xvzf geokerr.tar.gz

Then compile the source code file geokerr.f, for example using the gfortran compiler:

gfortran -ffixed-line-length-132 -O3 geokerr.f -o geokerr

The -ffixed-line-length option overrides the default behavior of cutting off input lines at character 80. The -O option optimizes the code for speed.

A simple way to run the code is to use the terminal to redirect input and output. For example,

./geokerr < > abgrid.out

inputs the example file "" The output can be found in "abgrid.out." See the manual for more details.

If you make use of these routines or would like to be informed of updates or bugs, please email me:

Eric Agol (agol AT