Transition inscriptions

There are five inscriptions that may be associated with a transition. All are optional:

• Transition name inscription
• Guard inscription
• Time inscription
• Code segment inscription
• Priority inscription

Transition inscriptions are created when you add/edit inscriptions for transitions.

Transition name inscription

The transition name inscription is an optional label that identifies the transition, and it may contain any sequence of characters.

Note: In order to enter the state space tool, transition names must fulfill certain requirements.

Guard inscription

Please see the help page for Guards.

Time inscription

A transition delay must be a positive integer expression. The expression is preceded by @+, and this means that the time inscription has the form @+ delay-expr. Before a time inscription has been added, the default text for the inscription is @+.

Default time inscription

Time delay is always added relative to the current time. For example, if current time is 10 and the time delay is @+2, then the time stamp of tokens sent to the output places will be 12. A missing time inscription is equivalent to a zero delay.

The time delay expression can use all the CPN variables of the corresponding transition. This means that the time delay may depend upon the token values for input and output tokens.

Token dependent time delay

Moreover, the expression may, via calculated CPN variables, depend upon reference variables and input files. The time inscription may also use functions, including, e.g. user-defined functions, the random function, the time function, and the random distribution functions.

Token dependent time delay

Examples of time inscriptions can be found in the Timed Protocol example.

Code segment inscription

Please see the help page for Code segments.

Priority inscription

A transition priority must be a non-negative integer expression. The lower the value, the higher the priority. Hence, a transition with priority value 1 has priority over a transition with priority value 2.

Related pages

Inscriptions and expressions, Naming_policy, Guards, Code segments