import os
import xml.etree.ElementTree as ET
import warnings
from dorie.utilities.warnings import VTKWarning
from dorie.utilities.vtktools import vtkfile
[docs]def read(files):
"""
Wrapper function that loops over the pvd files given and passes
them along to the reader function :func:`_read_single_pvd`.
:param files: Holds the file(s) to be read
:type files: str or list of str
"""
if isinstance(files,str):
files = [files]
values = []
for f in files:
if not isinstance(f,str):
raise TypeError("First argument must either be string of list of strings")
if not os.path.isfile(f):
raise RuntimeError("File {0} not found".format(f))
values.append(_read_single_pvd(f))
if len(values) == 1:
return values[0]
else:
return values
def _read_single_pvd(pvd):
"""
Traverses the PVD XML tree root given in ``root``.
Assumes the structure
.. literal::
<Collection> --> <DataSet timestep='...'>
:param str pvd: Path to the PVD file
.. note::
This function only parses ASCII encoded PVD files.
"""
error_base = "Error while reading PVD file {}:\n".format(pvd)
try:
xml_tree = ET.parse(pvd)
except ET.ParseError:
raise ET.ParseError(error_base + "Make sure the PVD "
"file is encoded in ASCII")
xml_root = xml_tree.getroot()
pvd_type = xml_root.attrib["type"]
if pvd_type != "Collection":
raise RuntimeError(error_base + "XML root attribute 'type' must "
"be 'Collection' (is: {})".format(root.attrib["type"]))
out = []
for collection in xml_root:
for data in collection:
if data.tag == "DataSet":
if "file" in data.attrib:
f = data.attrib["file"]
else:
raise RuntimeError(error_base + "Encountered DataSet without 'file' attribute")
vtk = vtkfile.VTKFile(f)
if "timestep" in data.attrib:
vtk.set_time(float(data.attrib["timestep"]))
else:
raise RuntimeError(error_base + \
"Encountered DataSet without 'timestep' attribute")
out.append(vtk)
else:
raise RuntimeError(error_base + "Unexpected tag: {0} (expected "
"DataSet)".format(dataArray.tag))
return out