SWMM - Control Rules - Format of the Rules

Each control rule is a series of statements of the form:

 RULE rule_id
 IF condition_1
 AND condition_2
 OR condition_3
 AND condition_4
etc.
 THEN action_1
 AND action_2
etc.
 ELSE action_3
 AND action_4
etc.
 PRIORITY value

Where keywords are shown in bold and rule_ID is an ID label assigned to the rule, condition_n is a condition clause, action_n is an action clause, and value is a priority value (for example, a number from 1 to 5).

Each rule clause must begin with one of the bolded keywords shown above, and only one clause per line is allowed.

Only the RULE, IF, and THEN parts of a rule are required; the ELSE and PRIORITY parts are optional.

Blank lines between clauses are allowed, and any text to the right of a semicolon is considered a comment.

When mixing AND and OR clauses, the OR operator has higher precedence than AND, i.e.

IF A OR B AND C

is equivalent to:

IF (A OR B) AND C

If the interpretation should be:

IF A OR (B AND C)

Then this can be expressed using two rules as in:

 RULE A1
 IF A 
 THEN...

 RULE A2
 IF B  AND C 
 THEN...

The PRIORITY value is used to determine which rule applies when two or more rules require conflicting actions to be performed on a link. A conflicting rule with a higher priority value takes precedence over one with a lower value (for example, PRIORITY 5 trumps PRIORITY 1). A rule without a priority value always has a lower priority than one with a value. For two rules with the same priority value, the rule that appears first gets the highest priority.

Some observations regarding the clause editor of SOLIDOS:

You can add or remove the extra clauses (ELSE, AND, OR or line concatenator), but you cannot add or remove the ones that start with IF and THEN .
To add the ELSE, use the button Else
By default, each new rule added has priority 0 (lowest). When formatting the result, the value 0 is not added to the INP, so you can change this value by typing an appropriate value in the Rules box:

To add a new rule, use the button Add
To remove the selected rules, use the button Delete
Note that to write an expression that compares two values obtained from two different devices, two lines are needed, and in the second line, the cell of the concatenator column is empty:

The result will be:
```
RULE R01
IF NODE SU1 DEPTH > NODE KRO3001 DEPTH
```
To add the empty concatenator line, use the Add button
To remove the empty concatenator line (or those that have AND or OR), use the button Delete b>