This is a wrapper script for Maurits Haverkort's
SpaghettiPrimavera.f90.
It produces the same kind of plots but should provide a simpler
interface. Like SpaghettiPrimavera.f90, it needs a$case.klist_band
and a corresponding $case.qtl file; it also reads $case.struct if
present.
If it exists, $case.qtl[up|dn]_band is preferred over $case.qtl[up|dn].
(Wien2k does not use .qtl_band but it is often convenient to rename
a .qtl file intended for band structures.)
See prima.py -h and prima.py (executed in a suitable Wien2k
directory) for usage hints.
Suppose we are interested in the t2g and eg contributions of the first inequivalent atom in the struct. A typical command line might be
prima.py 1:D-t2g:5,0,0:3 1:D-eg:0,0,5:3 -o prima.ps
if that atom has ISPLIT=2. If instead it has ISPLIT=8, the
command would read:
prima.py 1:DXY++DXZ++DYZ:5,0,0:3 1:DX2Y2++DZ2:0,0,5:3 -o prima.ps`
which is an abbreviated form of
prima.py 1:DXY:5,0,0:3 1:DXZ:5,0,0:3 1:DYZ:5,0,0:3 \
1:DX2Y2:0,0,5:3 1:DZ2:0,0,5:3 -o prima.ps
Each of the non-option arguments names an atom, an orbital, a color, a
thickness increment, and a description for the (optional) legend;
these tokens are separated by colons :, and each of them may be
empty.
The ampersand & combines two orbitals or two sites. Since it must
be escaped in most shells, a double plus sign ++ may be used instead
(a single + appears in some orbital descriptions in .qtl files).
For both the atom and the orbital specification, you can use a number
(in the sequence of $case.struct or $case.qtl) or a name (labels
as given in the same files). Furthermore, the following special atom
names are accepted:
all→ all atomsistl→ the interstitialZ$N→ all atoms with atomic number$N$Sy→ the atomic symbol expands to all atoms of that element
The atomic symbol applies only if you have several inequivalent atoms of the same element. As long as you follow the Wien2k convention for the struct labels (atomic symbol in the first two places, a number in the third), there can be no ambiguity with these special cases.
All atom and orbital specifications are case insensitive.
Colors can be named in three ways: as a comma-separated triple r,g,b
of red, green, blue values (nominally ∈ [0, 1]), in HTML-type
hexadecimal notation #RRGGBB, or one of the 147 color names defined
in SVG.
The QTL values from Wien2k, when the interstitial is included, are
normalized to 1, but how much of this weight is contained in a
particular muffin-tin sphere depends on a number of things. This
leads to a “normalization problem”; since there is no general
solution, prima.py simply multiplies the colors and thickness
increments by the QTL values and adds them. Therefore, it can be
useful to have r,g,b > 1. To make this easier, the color may be
prefixed by a factor: $f × $color.
In general, colored spaghetti are not a quantitative tool, and care must be taken in their interpretation, especially concerning the normalization and mixing of colors.
The options -m|--mix-spins and -j|--join-spins may be used to
combine data from two ‘qtl’ files (normally up and dn spin) in one
plot. While -m adds the character from the two files together and
imposes the energies to be the same, -j draws separate lines.
The spin can be selected by appending ↑ / ↓ / ↑↓ (or -up /
-dn / -updn) to a regular atom specification, e.g. 1↑, all-dn.
The file names default to $case.qtl{up,dn}_band and may be set by
giving --qtl twice.
The option -C|--config-file may be used to read options from a file
in addition to the command line. Each line in the config file(s)
should contain one option and, if applicable, its argument, separated
by whitespace. Any option valid on the command line may be used,
leading dashes may be omitted. For instance, if, by default, you want
to suppress the minor ticks, add a legend, and output to
$case_prima.ps, then put the following into ~/.prima
minor-ticks 0
write-legend
out-suffix _prima.ps
and add
alias prima.py="prima.py -C ~/.prima"
to your ~/.bashrc or equivalent. Beside a global config file, it
can also be useful to have per-directory configuration. This could be
implemented by
alias prima.py='prima.py $(test -e .prima && echo "-C .prima")'
Parsing of the config files is primitive. Lines are skipped if they
are empty or start with a hash #. Leading whitespace and whitespace
between option and argument is stripped, but trailing whitespace is
preserved.
To download prima.py, go to the GitHub page
and download from master for the cutting-edge version, or get the
latest release if you
prefer a stabler version.
prima.py needs Python 2, NumPy, F2PY (which is now part of NumPy), and
a modern Fortran compiler. I tested it with the following versions:
Running make in the prima directory should produce the file
sppv.so. Python must be able to find this file, and the file
webcolors.py. This is easiest if you create a symlink to prima.py
in some directory in your $PATH, or add the prima directory to
your $PATH.
In the simplest case, the whole procedure is accomplished by the commands
git clone https://github.com/eassmann/prima.py.git
cd prima.py
make
ln -sr prima.py $BIN
where $BIN ∈ $PATH.
The wiki has a set of
example plots
made with prima.py. Questions regarding the usage of prima.py could
be appropriate for the Wien2k mailing list.
Bug reports and fixes, suggestions, and so on should be submitted via GitHub as Issues or Pull Requests.
Thanks to Maurits for letting me build upon his code.
Hex colors and color names are handled by the webcolors module,
written by James Bennett.
Thanks to Peter Blaha and Manuel Zingl for valuable comments on previous versions.
prima.py was developed at Vienna
and Graz Universities of Technology.