Description of the low level Petri net editor window
The low level net editor is a Petri net editor with an integrated simulator offering some Petri box specific features.
The main part of the editor window can be used as a drawing canvas for creating and editing low level Petri nets.
The functionality of the menu bar is described in the next section.
The name of the currently edited LL net is displayed underneath the menu bar on the left hand side.
The current mode of the net editor is displayed underneath the menu bar on the right hand side.
If the editor is in Edit Mode the following can be done:
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- Places can be created by pressing the p -key at the desired position of the drawing canvas.
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- Transitions can be created by pressing the t -key at the desired position of the drawing canvas.
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- Arcs can be created by pressing the a -key first and selecting the place (transition) and the transition (place, resp.) with the left mouse button afterwards.
Note: If you click to quickly, the first node may jump towards the second node.
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- Comments can be created by pressing the c -key at the desired position of the drawing canvas. The dialog box is opened to edit the text.
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- An object (place, transition, arc, comment or annotation -- like name or meaning) can be selected by a click with the left mouse button.
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- A selected object can be moved by holding the left button down while moving the mouse.
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- A multi-selection of places and transitions can be extended by a click on another place or transition while the shift key is held down.
... A multi-selection can be deleted by pressing the del key.
... A multi-selection can be moved by holding down the left mouse button (after its last extension) while moving the mouse.
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- An area can be selected by enframing it using the middle mouse button. (If you have a mouse with only two buttons you can probably emulate this by clicking both buttons at the same time).
... An area can be deleted by pressing the del key.
... An area can be moved by the left mouse button (after clicking somewhere in the area without hitting an object).
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- The place dialog window can be opened by a double-click with the left mouse button on a place. Thus the name, the meaning, the initial and the current marking and the status of the place can be changed. The name must be unique w.r.t. the other places of the net; this is checked by the editor.
Note: The (global) current marking must not necessarily be reachable from the (global) initial marking.
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- The transition dialog window can be opened by a double-click with the left mouse button on a transition. Thus the name and the meaning of the transition can be changed. The name must be unique w.r.t. the other transitions of the net; this is checked by the editor.
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- The arc dialog window can be opened by a double-click with the left mouse button on a arc. Thus the weight of the arc can be changed. The weight of the arc (in terms of LL nets) is the cardinality of the variable multiset of this arc (in terms of HL nets). The unique name is generated automatically and cannot be changed.