| Author | Message | ||
     Kai Häberle (wharfish) New member Username: wharfish Post Number: 2 Registered: 07-2009 |
Hello Mr.Nelson, when I include an If-Then statement in my file, it only slows the calculation down but doesn't show the expected effect. Is there a proper way to include these statements in FlexPDE? Greetings | ||
| Marek Nelson (mgnelson) Moderator Username: mgnelson Post Number: 139 Registered: 07-2007 |
IF-THEN constructs should be used with extreme caution. They can often cause trouble for the solver if the value is not continuous through the switch point. It is much better to use one of the alternatives : RAMP, URAMP or SWAGE. See the Help section "Technical Notes | Avoid Discontinuities" (online at http://www.pdesolutions.com/help/index.html?discontinuities.html ). Without knowing what the "expected effect" is, I cannot offer an explanation why you do not observe it. The calculation is likely slow due to the discontinuity. Again, I cannot be sure without knowing more specifics. |