vector(lines) to rast II

Dear Grass users:
     Thank you to solve my question. But When I use "v.to.rast"
to transfer the Vector map to Raster map. It shows "Processing lines ...
  Floating exception (core dumped)" and no raster map occur. I use v.digit to
Lable my vector map(only contain lines) and Bulk them all in single catagory.
And use g.region to set the region of vector map.
I don't know why it happened. Does anyone know what's going on ? Can you help me?
Thanks a lot in advance

| Hung-Yue Lin , Email:hylin@ev004.ev.nctu.edu.tw
| Institute of Environmental Engineering Voice:011-886-35-712121-2929
| National Chiao Tung University Voice:011-886-35-712171x2928
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