Qbox Implemention of Magnetic Field

Qbox implementation without magnetic field

How wave function is distributed among processors

https://wiki.alcf.anl.gov/index.php/Qbox#Performance_Notes

• Fourier space (sphere)

• Real space (cube)

Qbox implementation with magnetic field

Retrive current working version

To retrieve the current implementation version of Qbox (within the Magnetic project), do

 cd ~/prj
 svn co --username USERNAME https://micro.stanford.edu/svn/Qbox

a directory named ./Qbox with the sources will be created in the current directory.

Revision history is available at https://micro.stanford.edu/viewvc/Qbox/

How wave function is distributed among processors

• Fourier space (cube)

• Real space (cube)

How Fourier transform is performed

real, intermediate, reciprocal spaces

Dumping the Hartree potential

Sometimes it is useful to obtain the self consistent Hartree potential, either to do a calculation on top of it or to have an intuition of the effective potential that electrons are subjected to.

Log of major changes

• Removed non-FFTW macro code in 'FourierTransform.C' to clean up the code.

• Removed ESSL and internal-FFT portions in FourierTransform::bwd and ::fwd

Code Style

Some new files were created to implement the magnetic portion, the style can be enforced by applying this command

indent \
  -i8 -l160 \
  --braces-on-if-line \
  --braces-on-struct-decl-line \ 
  --cuddle-do-while --cuddle-else \
  --no-blank-lines-after-declarations --no-blank-lines-after-procedures \
  --dont-break-function-decl-args \
  --no-space-after-function-call-names --no-space-after-parentheses \
  --dont-break-procedure-type \
  --no-space-after-for --no-space-after-if --no-space-after-while \
  --dont-space-special-semicolon  qbox.hpp

GNU Indent doesn't work perfectly with C++, it gets confused but comment ending in parenthesis and with angle brackets in templates. An alternative is to use bcpp

cp qbox.hpp.save qbox.hpp && \
~/usr/bin/bcpp -bcl -cc 80 -t -tbcl -nbbi qbox.hpp qbox.hpp.bcpp && \
mv -f qbox.hpp.bcpp qbox.hpp

Which respect almost perfectly the desired style (except that curly brackets appear in new lines), plus inline comments are moved to column 80.

A third alternative that work flawlessly for C++ is astyle:

~/usr/bin-hera/astyle \
 --brackets=attach \
 --indent=tab --indent-col1-comments \
 --unpad-paren \
 --delete-empty-lines \
 --add-brackets \
 --keep-one-line-statements \
 --convert-tabs \
 --align-pointer=type qbox.hpp

Which also gives (for me) a perfect style, except that curly brackets have a space before them and comments are not aligned to column 80.

The advantage of GNU Indent over the other two is that GNU Indent is installed by default in most systems.

To make the file VI and Emacs friendly, add the following modelines at the end of the file

...  file here
// Editor modelines  -  http://www.wireshark.org/tools/modelines.html
// Local variables:
// c-basic-offset: 4
// tab-width: 4
// indent-tabs-mode: t
// truncate-lines: 1
// End:
/* vim:set ft=cpp ts=4 sw=4 sts=4 nowrap: cindent: */

In this way Emacs, VI and gedit will open the code in a manner that can be nicely viewed and edited compatible with the style.