QuantumATK Forum

QuantumATK => General Questions and Answers => Topic started by: zhangguangping on April 30, 2016, 16:26

Title: Possible bug in VNL
Post by: zhangguangping on April 30, 2016, 16:26
Dear QW stuff,

I find a possible bug in VNL.
VNL:  2015.1.5b36b25
Platform:  windows 10 x64
Description: When you set the parameters in “New Calculator” of the "Script Generator",  the "Density mesh cut-off" can not be changed under the card "Basic device", it always go back to the default value 75 Hartree when you come back to this “Basic device” card, until you set the value in the card "Numerical accuracy parameters". That is to say,  the "Density mesh cut-off" can not use the value set in the card "Basic device", and only use the value set in the card "Numerical accuracy parameters".

With best regards,

Guangping
Title: Re: Possible bug in VNL
Post by: Anders Blom on April 30, 2016, 23:57
I know what you mean, and it can be a bit confusing, but it's technically not 100% a bug, it's by design. Also, what you describe is not correct, actually. However, what you probably observed (without realizing it) is that if first set the cut-off, and then change the basis set, then the cut-off gets reset to 75 H. This is partly on purpose, we attempt to prevent the user from using a too low cut-off, but on the other hand it is indeed a (known) bug that if you set it to higher than 75, it is still set to 75. However, if you first select the basis set, and then the cut-off you can perfectly well change the density mesh cut-off on both the Basic and Numerical accuracy parameters tabs.
Title: Re: Possible bug in VNL
Post by: zhangguangping on May 1, 2016, 00:53
Dear Anders,

Yeh, that it is.

However, the Basic device is fllowed by "Basis set/exchange correlation".

With best regards,

Guangping