I encountered an error when running an OpenFAST model with the latest MacOS version of OpenFAST (installed with Homebrew). The same model runs fine on Windows with OpenFAST v3.5.2 (pre-compiled binaries).
The error seems caused by Hydrodyn:
FAST_InitializeAll:HydroDyn_Init:Waves_Init:VariousWaves_Init: The random number generator in use differs from the original code provided by NREL. This pRNG uses 8 seeds instead of the 2 in the HydroDyn input file.
HydroDyn_Init:WAMIT_Init:Error reading line from WAMIT file
OpenFAST encountered an error during module initialization.
Simulation error level: FATAL ERROR
Do you know what is causing this error?
Dear @Alessandro.Fontanell,
The first message about the random number generator is just a warning.
The actual error is the last message about an error reading a line from the WAMIT file, which would be caused if the WAMIT data file in the *.1 file is not formatted properly.
Best regards,
Hi Jason,
thank you for the help. I inspected the .1 file and I did not find anything wrong. The same file runs fine in Windows. Is it possible the scientific notation is not valid in the MacOS version of HydroDyn?
Dear @Alessandro.Fontanell,
For the periods that are zero and negative (implying infinite and zero frequency), the radiation damping (5th column in the *.1 file) is always zero and I know WAMIT leaves these fields blank rather than reporting zeros as in your example. HydroDyn assumes this 5th column is blank as well. If you delete the 5the column for the zero and negative periods, does OpenFAST compiled on MacOS work as expected? (If so, perhaps the Windows compiler is a little more forgiving.)
Best regards,
Dear @Jason.Jonkman,
I found the issue is in the DOF columns (for example the 2nd and 3rd of the .1 file). Apparently, the MacOS version does not accept the scientific notation here but requires integer numbers. (1 instead of 1.0000000e+00). Zeros in the 5th columns for zero and negative periods are accepted.
As an old time MacOS user, I hope this helps going towards a sound pre-compiled OpenFAST (and related codes) distribution for every operating system 
Thank you for your support and best regards.
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