Opened 12 years ago

Last modified 8 years ago

#2428 new defect

numerical instability — at Initial Version

Reported by: Willi Braun Owned by: somebody
Priority: high Milestone: Future
Component: Run-time Version: trunk
Keywords: Cc:

Description

Following model behaves numerical instable:

loadString("
model testCFExpr1
  Real x;
initial equation
  der(x) = 3.14159/2;
equation
  sin(der(x)) = cos(x);
end testCFExpr1;
");

simulate(testCFExpr1, stopTime=10, tolerance=1e-4);
val(x,0);
val(x,10);

val(der(x),0);
val(der(x),10);

simulate(testCFExpr1, stopTime=10, tolerance=1e-5);
val(x,0);
val(x,10);

val(der(x),0);
val(der(x),10);

simulate(testCFExpr1, stopTime=10, tolerance=1e-6);
val(x,0);
val(x,10);

val(der(x),0);
val(der(x),10);

simulate(testCFExpr1, stopTime=10, tolerance=1e-7);
val(x,0);
val(x,10);

val(der(x),0);
val(der(x),10);

simulate(testCFExpr1, stopTime=10, tolerance=1e-8);
val(x,0);
val(x,10);

val(der(x),0);
val(der(x),10);

Change History (1)

by Willi Braun, 12 years ago

Attachment: testCFExpr1.mos​ added
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