prismmodelchecker / prism

The main development version of the PRISM model checker.
http://www.prismmodelchecker.org/
GNU General Public License v2.0
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Wrong result for CTMC-Until with >=t bound (explicit engine) #9

Closed kleinj closed 8 years ago

kleinj commented 8 years ago

For example, for prism-tests/functionality/verify/ctmcs/rewards/ctmc_rewards2.sm and property P=?[ F>=0 s>3 ], the explicit engine yields Infinity, while the symbolic engines yield a value ~1/3.

This is due to performing Until computations using the DTMC model checker directly on the CTMC instead of on the embedded DTMC here and here.

This only happens if there is a lower bound but no upper bound, i.e., for F>=t target or a U>=t b, CTMCs and the explicit engine.

kleinj commented 8 years ago

Fixed in SVN 11768.