UPPAAL v.4.1.19：作为函数参数的时钟是否有方法/属性？能否获取上下界？

Great question! Let me break down what you can and can’t do with clock references in UPPAAL v4.1.19 functions—since the documentation can be a bit sparse on this specific detail.

First, a critical point to wrap your head around: UPPAAL clocks don’t have inherent upper/lower bound properties attached to the clock object itself. Those bounds are defined in your model’s location invariants or transition guards—they’re static constraints applied to the clock in specific contexts, not built-in attributes of the clock variable. So there’s no direct method or property like cl.getUpperBound() you can call in a function to pull those values.

That said, here’s what you can do with a clock reference in a UPPAAL function:

• Read the clock’s current runtime value: You can directly assign the clock to a numeric variable to grab its current time value. For example:

  void access_clock(clock & cl) {
      double current_time = cl;
      // Use current_time in calculations or conditional checks
  }
  

• Reset the clock: You can set the clock to 0 just like you would in a transition’s reset action:

  void reset_clock(clock & cl) {
      cl = 0;
  }
  

• Compare the clock against fixed values: You can use the clock in boolean conditions (just like in guards) to check its state relative to constants:

  bool is_clock_over_threshold(clock & cl) {
      return cl >= 7; // Checks if the clock has reached 7 time units
  }
  

If you need to work with the bounds you’ve defined for a clock in your model (like invariants), the practical workaround is to define explicit constants for those bounds and reuse them everywhere. For example:

const int MY_CLOCK_UPPER_LIMIT = 12;
const int MY_CLOCK_LOWER_LIMIT = 0;

// In your location invariant: cl <= MY_CLOCK_UPPER_LIMIT
// In your function:
void validate_clock(clock & cl) {
    if (cl < MY_CLOCK_LOWER_LIMIT || cl > MY_CLOCK_UPPER_LIMIT) {
        // Handle out-of-bounds logic here
    }
}

This approach keeps your bounds consistent across the model and lets you reference them directly in functions.

内容的提问来源于stack exchange，提问作者O. K.