[yt-users] Problem in accessing ramses data

[Junhwan Choi (최준환)]

Hi yt user,

Here I try to make some plots with centering to the densest cell using
following script:
=====================
from yt.mods import *

ds = load("/lustre/widow2/proj/ast031/test11_rhd_fesc=0.05/output_00048/info_00048.txt",
fields = ["Density","x-velocity", "y-velocity",
"z-velocity","Pressure","Metallicity","HI"])
center = ds.h.find_max("Density")[1]

pw = ProjectionPlot(ds, "x", "Density", weight_field="Density", center=center)
pw.zoom(1.01)
pw.save("allviewGas")
pw = ProjectionPlot(ds, "y", "Density", weight_field="Density", center=center)
pw.zoom(1.01)
pw.save("allviewGas")
pw = ProjectionPlot(ds, "z", "Density" , weight_field="Density", center=center)
pw.zoom(1.01)
pw.save("allviewGas")
=====================

and, I got the following error message
  File "VisFrame.py", line 4, in <module>
    den_center = ds.h.find_max("Density")[1]
  File "/autofs/na3_home1/jhchoi/common/src/yt-hg/yt/geometry/oct_geometry_handler.py",
line 59, in find_max
    mv, pos = self.find_max_cell_location(field, finest_levels)
  File "/autofs/na3_home1/jhchoi/common/src/yt-hg/yt/geometry/oct_geometry_handler.py",
line 69, in find_max_cell_location
    source.quantities["MaxLocation"](field)
  File "/autofs/na3_home1/jhchoi/common/src/yt-hg/yt/data_objects/derived_quantities.py",
line 79, in __call__
    return self.c_func(self._data_source, *retvals)
  File "/autofs/na3_home1/jhchoi/common/src/yt-hg/yt/data_objects/derived_quantities.py",
line 666, in _combMaxLocation
    i = np.argmax(args[0]) # ma is arg[0]
  File "/ccs/home/jhchoi/common/lib/python2.7/site-packages/numpy/core/fromnumeric.py",
line 738, in argmax
    return argmax(axis)
ValueError: attempt to get argmax of an empty sequence

In order to check whether the simulation Density output is messed up,
I replace "center = ds.h.find_max("Density")[1]" to "center=[0,0,0]",
then I am able to make Density projection.
This test suggest that the Density output in the simulation is
alright, but the "ds.h.find_max("Density")[1]" has problem.
Does anyone know how to resolve it?

Thank you in advance,
Junhwan