RAM PARABOLIC EQUATION
This source code is a translation in optimized C of the original ram code from Dr. David C. Calvo. See readme.orig for original instructions.
The original code shipped five sources:
The aim of this project is to make these program run faster by using several optimization techniques, while keeping the original behavior. This implies a move to the C language.
Download the latest release with the following link: ramsurf-1.0.tar.gz
You can install all the ramsurf variant as well as the headers using:
sudo make install
To turn on the vectorized C code, run:
make CFLAGS="-O2 -march=native"
All the traditional autotool flags work, including not building in the sources.
Compare the output produced by the FORTRAN code and the C code using:
Using the Ramsurf Program
The C version mimics the FORTRAN interface and assumes all inputs are described in ram.in. It outputs two files: lt.line as plain text and tl.grid using the binary format used by FORTRAN.
The input format is the same as the one described in readme.orig:
# sample config. The first line is a header and is skipped. freq zs zr #frequency in Hz, source depth, receiver depth (data at this depth goes into tl.line) rmax dr ndr #maximum range (rmax), range step (delta r or dr), ndr (writes output every ndr range steps) zmax dz ndz zmplt #maximum depth of the whole computational domain (zmax), depth step (dz), ndz (output data at every ndz vertical point at a given range), vertical extent of the domain to output in tl.grid (zmplt). c0 np ns rs # reference sound speed, number of Pade terms (np), # of stability constraints (ns), radius of stability constraint (rs) surface_range0 surface_depth0 # surface modeling ... surface_rangeN surface_depthN -1 -1 # END of SECTION marker bathymetry_range0 bathymetry_depth0 #bathymetry modeling ... bathymetry_rangeM bathymetry_depthM -1 -1 ssp_depth0 ssp_value0 # sound speed profile in water ... -1 -1 bssp_depth0 bssp_value0 # sound speed profile in bottom ... -1 -1 bd_depth0 bd_value0 # density of bottom ... -1 -1 ba_depth0 ba_value0 # attenuation of bottom ... -1 -1 optional_range # if given, starts a new ssp description starting from this range, otherwise the previous values are valid for all remaining ranges [...]
Using the Ramsurf Library
The C version can be used as a C library. Link with -lramsurflib and include ramsurf.h. The interface documentation is contained in the header file.