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avoid sharp picks _convergence problem

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Dear All,
Do you have any idea how I can smooth this expression?

B=1/A*(A!=0)+0*(A==0)

Many thanks in advance,
Elham

2 Replies Last Post 05.01.2011, 12:31 GMT-5
Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)

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Posted: 1 decade ago 05.01.2011, 10:08 GMT-5
Hi

have you tried

1/(A+eps)

if A is only >0 or only <0 it could work

or

if(A==0,0,1/A)

this might work

See the users Guide p81:
Use the if operator to avoid illegal operations. For example, if(x==0,1,sin(x)/x) is a valid and continuous expression for all values of x, including x = 0.

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Good luck
Ivar
Hi have you tried 1/(A+eps) if A is only >0 or only

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Posted: 1 decade ago 05.01.2011, 12:31 GMT-5
Thank you ivar. what I've written and you suggest seem to be equivalant. apparantly, this kind of if condition shouldn't make convergence problem. I need to look for other sources of problem.
regards,
Elham
Thank you ivar. what I've written and you suggest seem to be equivalant. apparantly, this kind of if condition shouldn't make convergence problem. I need to look for other sources of problem. regards, Elham

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