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the plan

tempestpy_adaptions
tomjanson 9 years ago
committed by Tom Janson
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  1. 22
      src/utility/shortestPaths.md

22
src/utility/shortestPaths.md

@ -39,6 +39,28 @@ target group is required in the constructor. (It would have been possible to
allow for interchangeable target groups, but I don't anticipate that use
case.)
#### Special case: Using Matrix/Vector from SamplingModel
The class has been updated to support the matrix/vector that `SamplingModel`
generates (as an instance of a PDTMC) as input. This is in fact closely
related to the target groups, since it works as follows:
The input is a (sub-stochastic) transition matrix of the maybe-states (only!)
and a vector (again over the maybe-states) with the probabilities to an
implied target state.
This naturally corresponds to having a meta-target, except the probability
of its incoming edges range over $(0,1]$ rather than being $1$.
Thus, applying the term "target group" to the set of states with non-zero
transitions to the meta-target is now misleading (I suppose the correct term
would now be "meta-target predecessors"), but nevertheless it should work
exactly the same. [Right?]
In terms of implementation, in `getEdgeDistance` as well as in the loop of
the Dijkstra, the "virtual" edges to the meta-target were checked for and
set to probability $1$; this must now be changed to use the probability as
indicated in the `targetProbVector` if this input format is used.
### Minimality of paths
Secondly, we define shortest paths as "minimal" shortest paths in the
following sense: The path may not visit any target state except at the

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