Changes between Version 5 and Version 6 of LanguageChanges

Timestamp:

Jan 12, 2007, 1:08:49 PM (16 years ago)

Author:

Rafael de Pelegrini Soares

Comment:

Added switch suggestion

LanguageChanges

@@ -151 +151 @@
 ||Who || Opinion || Why ||
 ||Rafael || '''option 3''' || With option 3 we have a clear distinction between the graphical interface and the models ||
+
+== Switcher for equations ==
+
+Currently, continuous-discrete modeling is supported in EMSO using the '''if''' statement.
+But some more complex situations cannot be modeled with '''if'''.
+
+For example, a safety valve which opens if the pressure is higher than 2 atm but closes only when the pressure is lower than 1 atm.
+This situation cannot be modeled by a simply '''if'''. For this case, a State Transition Network (STN) is needed.
+
+For this case the '''Switcher''' is proposed, usage:
+{{{
+#!mso
+Model SafetyValve
+    PARAMETERS
+    mode as Switcher(Valid = ["closed", "opened"], Default = "closed")
+    ...
+    EQUATIONS
+    switch(mode)
+    case "closed":
+       flow = 0 * "mol/h";
+       change to "opened" if P>2*"atm";
+    case "opened":
+       flow = k*sqrt(P - Pout);
+       change to "closed" if P<1*"atm";
+    end
+    ...
+end
+}}}
+
+In the piece of code above there are the following news:
+ * A new basic type called '''Switcher'''
+ * The '''Switcher''' type has an extra attribute called '''Valid''' which are the valid values for the switcher
+ * There is a '''switch''' command which can be used in the EQUATIONS
+ * There is a '''change to''' command which can be used inside a '''case''' of a '''switch'''
+
+||Who || Opinion || Why ||
+||Rafael || '''agreed''' || proposed the change ||