Residual drop calculation

Anna Tian · August 18, 2014, 22:29

Textbook or commercial software tutorial usually give convergence criteria as listed below.

1) The parameter we concern doesn’t change with more iterations.
2) The residual drop by 3-5 orders from the residual value of the first step ‘or’ the maximum residual value.

I’m confusing about whether shall I calculate the drop order by the residual value of the first step or the maximum residual value? Sometimes they are very different. The maximum residual value could be much higher than the residual value of the first step.

What is the theory behind this 'order drop calculation' criteria? What do 'the residual value of the first iteration step' and 'the maximum residual value' actually represent?

Anna Tian · August 21, 2014, 10:36

Could anyone answer me this question?

August 18, 2014, 22:29	Residual drop calculation	#1
Anna Tian Senior Member Meimei Wang Join Date: Jul 2012 Posts: 494 Rep Power: 16	Textbook or commercial software tutorial usually give convergence criteria as listed below. 1) The parameter we concern doesn’t change with more iterations. 2) The residual drop by 3-5 orders from the residual value of the first step ‘or’ the maximum residual value. I’m confusing about whether shall I calculate the drop order by the residual value of the first step or the maximum residual value? Sometimes they are very different. The maximum residual value could be much higher than the residual value of the first step. What is the theory behind this 'order drop calculation' criteria? What do 'the residual value of the first iteration step' and 'the maximum residual value' actually represent? __________________ Best regards, Meimei Last edited by Anna Tian; August 20, 2014 at 21:47.

August 21, 2014, 10:36		#2
Anna Tian Senior Member Meimei Wang Join Date: Jul 2012 Posts: 494 Rep Power: 16	Could anyone answer me this question? __________________ Best regards, Meimei

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