FDSReader
Fast and easy-to-use Python reader for FDS data
FDS Version Compatibility
| fdsreader | FDS 6.7 | FDS 6.8 | FDS 6.9 | FDS 6.10 | FDS 6.11 |
|---|---|---|---|---|---|
| ≤ 1.11.9 | ✅ | ✅ | ✅ | ⚠️ (Geometry bug) | ⚠️ (Geometry bug) |
> 1.11.9 (unreleased, master) |
✅ | ✅ | ✅ | ✅ | ✅ |
Tested against FDS outputs. If you find a compatibility issue please open an issue.
Installation
The package is available on PyPI and can be installed using pip:
pip install fdsreader
The Jupyter explorer needs a plotting stack, which is an optional extra:
pip install "fdsreader[notebook]"
Its command line counterpart needs nothing beyond numpy and is always installed.
FDS Version 6.7.5 and above are fully supported. Versions below 6.7.5 might work, but are not guaranteed to work.
Usage example
import fdsreader as fds
# Creates an instance of a simulation master-class which manages all data for a given simulation
sim = fds.Simulation("./sample_data")
# Examples of data that can be easily accessed
print(sim.meshes, sim.surfaces, sim.slices, sim.data_3d, sim.smoke_3d, sim.isosurfaces, sim.particles, sim.obstructions)
More advanced examples can be found in the respective data type directories inside of the examples directory.
Configuration
The package provides a few configuration options that can be set using the settings module.
fds.settings.KEY = VALUE
# Example
fds.settings.DEBUG = True
| KEY | VALUE | Default | Description |
|---|---|---|---|
| LAZY_LOAD | boolean | True | Load all data when initially loading the simulation (False) or only when specific data is needed (True). |
| ENABLE_CACHING | boolean | True | Cache the loaded simulation to reduce startup times when loading the same simulation again. |
| DEBUG | boolean | False | Crash on non-critical errors with an exception (True) or output non-critical errors as warnings (False). |
| IGNORE_ERRORS | boolean | False | Ignore any non-critical errors completely. |
Data structure
Beware that not all attributes and methods are covered in this diagram. For a complete documentation of all classes check the API Documentation below.
Explorer
fdsreader.explorer looks at a simulation without writing plotting code for it: a time
bar driving a 2D slice, and any number of device or HRR quantities plotted against time.
In Jupyter that is an interactive widget; in a terminal you can either explore it
interactively or draw a single view and exit.
In Jupyter
from fdsreader.explorer import explore
explorer = explore()
That renders the whole interface — a directory browser, the time bar, the slice on the left and the curves on the right. Browse to a case and press Load simulation.
explore("./sample_data") # skip the browser and load this case
explore(start_dir="/data/cases") # open the browser somewhere specific
explore(interactive_canvas=False) # static images instead of ipympl canvases
explore(caching=True) # allow the .pickle cache (writable data only)
explore() returns the explorer, so the simulation and the current selection stay
available in later cells:
sim = explorer.sim
explorer.current_time # where the time bar is, in seconds
explorer.selection # the curves currently ticked
explorer.field.frame(400) # the slice on screen, at time step 400
ipympl is optional; with it each plot gains a toolbar to zoom, pan and save. If the
plots come up as Failed to load model class 'MPLCanvasModel', its browser-side
extension is not loading — pass interactive_canvas=False.
In a terminal
The command line front end needs nothing but numpy, so it works over SSH on a machine with no plotting stack and no browser.
-i opens a full-screen interactive view, where the slice and the curves are chosen from
lists rather than named on the command line:
fdsreader-explorer-cli ./sample_data -i
| key | |
|---|---|
← → or h l |
step through time |
page up / page down |
ten steps |
home / end |
first / last step |
space |
play, pause |
+ - |
play speed |
f |
pick the slice from a list |
c |
pick the curves from a list (space ticks, enter accepts) |
[ ] |
previous / next slice |
g / s |
colour scale over the whole run / this step |
? |
help |
q |
quit |
Without -i it draws one view and exits, which is what you want in a script:
fdsreader-explorer-cli ./sample_data # what is in it
fdsreader-explorer-cli ./sample_data --list # slices and curves by name
fdsreader-explorer-cli ./sample_data --slice 0 --time 4.4 # draw a slice
fdsreader-explorer-cli ./sample_data --curve TC_1 --curve HRR
fdsreader-explorer-cli ./sample_data --json # for scripting
TEMPERATURE [C] — x = 0 m #0 · t = 4.401 s (step 630 of 749)
10.00 |
|
8.82 |
|
|
| ...
| .....
5.88 | .....
| ...:...
| .....
| ....
| ...
2.94 | .:..
| -.
| -:-.
| .-*:
| +%+.
0.00 | +#:
+------------------
-2.5 2.5 y [m]
scale 20 … 1412 ramp ' .:-=+*#%@' grid 18x18
--save FILE writes the current view as an image or an animation instead
(.png/.pdf/.svg/.gif/.mp4, needs matplotlib).
The interactive view uses curses, which is in the standard library everywhere except
Windows; there, pip install windows-curses provides it.
Slices are read one time step at a time, so stepping through a long run costs a few hundred kilobytes rather than loading the whole series into memory.
API Documentation
https://fdsreader.readthedocs.io
Releasing a new version
Versioning is handled automatically via Git tags using setuptools-scm.
# New release
git tag -a v1.12.0 -m "Version 1.12.0"
git push origin v1.12.0
This triggers the release workflow which builds the package and publishes it to PyPI.
Meta
- Jan Vogelsang – j.vogelsang@fz-juelich.de
- Marc Fehr - m.fehr@fz-juelich.de
- Kristian Börger - k.boerger@fz-juelich.de
- Prof. Dr. Lukas Arnold - l.arnold@fz-juelich.de
Distributed under the LGPLv3 (GNU Lesser General Public License v3) license. See LICENSE for more information.
https://github.com/FireDynamics/fdsreader
Contributing
See CONTRIBUTING.md for development setup, how to run tests, and the PR checklist.
3 maintainers
Metadata
3 maintainers
Release files for fdsreader 1.12.1
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