[Carpet] Error when recovering from a checkpoint file

[Ian Hinder]

On Thu, Aug 24, 2006 at 03:50:48PM -0500, Erik Schnetter wrote:
> On Aug 24, 2006, at 14:57:55, Nils Dorband wrote:
> 
> >Hi,
> >
> >I am having trouble to recover from a checkpoint file. I get the
> >following error:
> >
> >Activating thorn CarpetIOHDF5...Success -> active implementation  
> >IOHDF5
> >While reading characters from a stream:
> >    Character ',' expected, but not found.
> >    The next up to 100 available characters are "".
> >Input error while reading a bbox
> >Input error while reading a vector<>
> >    The following elements have been read so far: []
> >Input error while reading a vector<>
> >    The following elements have been read so far: []
> >Input error while reading a vector<>
> >    The following elements have been read so far: []
> >
> >
> >
> >Then the run stops. This happens with a run using Multipatch. I only
> >see the error on supermike. It is working just fine on a different
> >machine. I am wondering if someone encountered that problem before
> >and what the reason might be.
> 
> This is a parsing routine in Carpet.  It interprets e.g. the strings  
> that describe the grid structure.  These strings can be given as  
> parameters.  They are also stored in checkpoint files.  Apparently  
> the string is malformed or missing.

Do you have newlines in the parameter?  The currentl implementation
for checkpointing and recovery of parameters is not compatible with
parameters containing newline characters.  When you checkpoint, the
parameters from your simulation are written into one long string in
the HDF5 file, separated by newlines as the delimiters.  So the
parameters will be corrupted when read back in if they have newlines
in them.  One fix would be to modify the routine that writes out the
parameters to just replace newlines with spaces or empty strings.
Alternatively, just avoid putting newlines in your parameters.

-- 
Ian Hinder
hinder at gravity.psu.edu
http://www.gravity.psu.edu/~hinder