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Using step functions as initial values
Posted Jan 24, 2011, 1:01 a.m. EST Version 4.1 2 Replies
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Hi all
I am unable to implement a step function in my model. I have two domains, and the initial value in domain 1 is V and domain 2 is 0. How can i smooth the initial value from V to 0 at the interface of the two domains. I realize it is quite simple but I am unable to find out how to do this. Thanks
I am unable to implement a step function in my model. I have two domains, and the initial value in domain 1 is V and domain 2 is 0. How can i smooth the initial value from V to 0 at the interface of the two domains. I realize it is quite simple but I am unable to find out how to do this. Thanks
2 Replies Last Post Jan 24, 2011, 4:25 p.m. EST
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Posted:
1 decade ago
Hi
have you tried to implement the "Definitions - Funtions - step", you might need to add/subtract a little offset and change the slope defined on the second tab (closed by default)
--
Good luck
Ivar
have you tried to implement the "Definitions - Funtions - step", you might need to add/subtract a little offset and change the slope defined on the second tab (closed by default)
--
Good luck
Ivar
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Posted:
1 decade ago
Hi Ivar
I did not implement the step function the right way. After some research i figured it out. The step function has 4 inputs. The location (in my case a certain radial distance), the start value and end value ( for a variable, say, concentration) and then the interval where the variable is taken from the start value to the end value. Now when the step function is declared say as an initial value the syntax is step(argument). Since the argument i have chose is radical distance, it should be declared as step(r). It works out
I did not implement the step function the right way. After some research i figured it out. The step function has 4 inputs. The location (in my case a certain radial distance), the start value and end value ( for a variable, say, concentration) and then the interval where the variable is taken from the start value to the end value. Now when the step function is declared say as an initial value the syntax is step(argument). Since the argument i have chose is radical distance, it should be declared as step(r). It works out