LatticeFasterDecoder failed with "link_extra_cost == link_extra_cost"

[feihwu]

Hello everyone -
I successfully decode a prob output from accoustic model using lattice_faster_decoder.decode().

now I want to simulate the online decoding - I split the prob output into several chunks, each chunk has 50 frames.

For each chunk, I call the function lattice_faster_decoder.advanceDecoding() ( I changed the target_frames_decoded to ensure it is correct; and called lattice_faster_decoder.InitDecoding() once at the very beginning)

then in the processing the 2nd chunk, I get the error "failed: link_extra_cost == link_extra_cost".
which means the link_extra_cost is NaN in PruneForwardLinks(...).
any hints why this happen?

Thanks.

[feihwu]

figure out why - this NaN is caused by invalid index into the decodable->LogLikelihood(...).