tkarabela / ensight-reader

A pure Python reader for the EnSight Gold format

ensight-reader

This library provides a pure Python reader (with some writing capability) for the EnSight Gold data format, a common format for results of computational fluid dynamics (CFD) simulations. It also comes with a few CLI tools, notably ensight_transform which allows you to perform in-place scaling/translation/etc. of the geometry in your case.

The library designed for efficient, selective, memory-mapped access to data from EnSight Gold case – something that would be useful when importing the data into other systems. If you're looking for a more "batteries included" solution, look at vtkEnSightGoldBinaryReader from the VTK library (see docs for comparison).

Requirements

• Python 3.9+
• NumPy 1.21+

Installation

pip install ensight-reader

Example – Python API

import ensightreader
import numpy as np

case = ensightreader.read_case("example.case")
geofile = case.get_geometry_model()

part_names = geofile.get_part_names()           # ["internalMesh", ...]
part = geofile.get_part_by_name(part_names[0])
N = part.number_of_nodes

with geofile.open() as fp_geo:
    node_coordinates = part.read_nodes(fp_geo)  # np.ndarray((N, 3), dtype=np.float32)

variable = case.get_variable("UMean")

with variable.mmap_writable() as mm_var:
    data = variable.read_node_data(mm_var, part.part_id)
    data[:] = np.sqrt(data)                     # transform variable data in-place

Example – CLI

# increment X coordinate
ensight_transform --translate 1 0 0 sphere.case

# scale by 1000 (eg. m -> mm conversion)
ensight_transform --scale 1e3 1e3 1e3 sphere.case

# rotation matrix
ensight_transform --matrix \
    0 -1  0  0 \
    1  0  0  0 \
    0  0  1  0 \
    0  0  0  1 \
    sphere.case

# transform only "internalMesh" part
ensight_transform --translate 1 0 0 --only-parts internalMesh motorbike.case

To learn more, please see the documentation.

ensight-reader's Issues

filenames containing quotes "" getting double quotes '""'

I've been provided with an ansys output file that makes use of quotes for the filenames.

The encas file looks like this

FORMAT
type:  ensight gold
GEOMETRY
model: "filename.geo"
VARIABLE
scalar per element: uds_1_scalar                                     "filename.scl1"
vector per element: velocity                                         "filename.vel"
SCRIPTS
metadata: "filename.xml"

this leads to the files not being found as it looks like ensight-reader assumes these filenames don't have quotes so it makes a string with a double quote and errors

>>> case.get_variable(v[0])
Traceback (most recent call last):
 File "<stdin>", line 1, in <module>
 File "/home/j/miniforge-pypy3/envs/f4enix_dev/lib/python3.11/site-packages/ensightreader.py", line 1698, in get_variable
   self._variable_file_cache[cache_key] = self.variables[name].get_file(geofile=geofile, timestep=timestep)
                                          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 File "/home/j/miniforge-pypy3/envs/f4enix_dev/lib/python3.11/site-packages/ensightreader.py", line 1511, in get_file
   return EnsightVariableFile.from_file_path(path, variable_name=self.variable_name,
          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 File "/home/j/miniforge-pypy3/envs/f4enix_dev/lib/python3.11/site-packages/ensightreader.py", line 1251, in from_file_path
   with open(file_path, "rb") as fp:
        ^^^^^^^^^^^^^^^^^^^^^
FileNotFoundError: [Errno 2] No such file or directory: '"filename.scl1"'

I guess this is due to Ansys putting quotes where there should not be quotes

Code for writing variable file

@tkarabela ,

I was wondering how to write the variable file using the ensightreader library. I commented this on the issue you resolved here -
#4. However, I had not realized the issue had been closed.

My simple question is what attributes can I use to write the variable file?

Attribute Error

Hello,

I am not able to run the code provided for ensight-reader. I get this error - AttributeError: 'GeometryPart' object has no attribute 'read_coordinates'
Is there a specific attribute I should use? What is the solution?

ensight2vtk for nfaced

Hello, could you support the nfaced element type in ensight2vtk.py?

equivalent command for "part.read_nodes" in version "0.9.0"

Hi,

Is there a way to extract part node coordinates in version "0.9.0"? I'm using a complex container and therefore stuck with python 3.8

I'm trying:
with geofile.open() as fp_geo:
coords_interior = part_interior.read_nodes(fp_geo)

But I got AttributeError: 'EnsightGeometryFile' object has no attribute 'open'
This is not a problem for 1.11.0