Author Topic: Warning Message  (Read 2672 times)

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Offline davalenciah

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Warning Message
« on: November 29, 2011, 14:35 »
Hello

I was doing a DFT transport calculation and I got a message in the output file as:

################################################################################
# WARNING                                                                      #
#                                                                              #
# The computed multigrid residual is greater than the required accuracy.       #
#                                                                              #
# Computed residual :   1.81808e-12                                            #
# Required accuracy :   1.00000e-12                                            #
#                                                                              #
################################################################################

What parameter I should increase to reach the require accuracy?
the mess cut off?
k points or another one?


Thanks for your Help

Offline Anders Blom

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Re: Warning Message
« Reply #1 on: November 29, 2011, 15:49 »
If the residual is still so small it's absolutely nothing to worry about.

Offline esp

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Re: Warning Message
« Reply #2 on: January 18, 2012, 21:36 »
what if it is not that small?

The computed multigrid residual is greater than the required accuracy
# Computed residual :   5.79742e-09                                            #
# Required accuracy :   1.00000e-12 

Offline Anders Blom

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Re: Warning Message
« Reply #3 on: January 18, 2012, 21:39 »
That's still small :)

Offline Nordland

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Re: Warning Message
« Reply #4 on: January 19, 2012, 15:15 »
It means that another iteration in the multigrid solver would only improve the the solution of the Poisson equation for the electrostatic by a 1e-9 Hartree.

Offline abhi005

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Re: Warning Message
« Reply #5 on: November 12, 2014, 11:13 »
my residual error is shown below.what is INF0e.Is this error is quite small or i have to worry?

Computed residual :   1.#INF0e+000                                            #

Offline Anders Blom

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Re: Warning Message
« Reply #6 on: November 12, 2014, 12:58 »
Infinity is not quite small...

Offline abhi005

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Re: Warning Message
« Reply #7 on: November 12, 2014, 14:00 »
thanks anders blom for your reply....actually i didnt know that INF means infinity.