Description: Return Invalid Value. This function always returns an invalid value.
Returns: Invalid
Usage: Script or Steady State.
Format: Invalid()
Parameters: None
Comments: This function is useful to invalidate data that are found to be incorrect, or to disable statements or functions that will not execute with invalid parameters.
Examples:
x = Valid(Invalid());
This will set x to 0.
Another example of this function's usefulness follows:
Main [
If !Valid(a);
[
a = Scale(Rand(), 0, 1, -1000, 1000);
...
]
If Valid(a);
[
...
a = Invalid();
]
]
By toggling a between a valid and an invalid value, you can ensure that the two scripts in Main will take turns executing; it is not possible for a race condition to occur.
See Also: