fuefit 0.0.3-beta.2

*fuefit* fits engine-maps on physical parameters

Release:

x.x.x

Home:

https://github.com/ankostis/fuefit

Documentation:

https://fuefit.readthedocs.org/

PyPI:

https://pypi.python.org/pypi/fuefit

Copyright:

2014 European Commission (JRC-IET)

License:

EUPL 1.1+

The fuefit is a python package that calculates fitted fuel-maps from measured engine data-points based on parameters with physical meaning.

Introduction

Overview

The Fuefit calculator accepts engine data-points for as Input, (RPM, Power and Fuel-Consumption or equivalent quantities such as CM, PME/Torque and PMF) and spits-out fitted fuel-maps according to the following formula [1]:

\begin{equation*} (a + b*cm + c*cm**2)*pmf + (a2 + b2*cm)*pmf**2 + loss0 + loss2*cm**2 \end{equation*}

An “execution” or a “run” of a calculation along with the most important pieces of data are depicted in the following diagram:

       .-------------------.                         .--------------------------.
      /    Input-Model    /     ____________        /       Output-Model       /
     /-------------------/     |            |      /--------------------------/
    / +--engine         /  ==> | Calculator | ==> / +--engine                /
   /  +--engine_points /       |____________|    /  | +--fc_map_params      /
  /   +--params       /                         /   +--engine_map          /
 /                   /                         /    +--fitted_eng_points  /
'-------------------'                         '--------------------------'

The Input & Output Model are trees of strings and numbers, assembled with:

• sequences,

• dictionaries,

• class(pandas.DataFrame),

• class(pandas.Series), and

• URI-references to other model-trees (TODO).

Quick-start

Assuming a working python-environment, open a command-shell (ie in Windows use program(cmd.exe) BUT with program(python.exe) in its envvar(PATH)) and try the following commands

Install:

$ pip install fuefit --pre

Cmd-line:

$ fuefit --version
0.0.3-beta.2

$ fuefit --help
...

## Change-directory into the `fuefit/test/` folder in the  *sources*.
$ fuefit -I FuelFit_real.csv header+=0 \
    --irenames n_norm _ fc_norm \
    -I engine.csv file_frmt=SERIES model_path=/engine header@=None \
    --irenames \
    -m /engine/fuel=petrol \
    -O - model_path=/engine/fc_map_params \
    -m /params/plot_maps@=True

Start-menu:

$ fuefit --winmenus ## Windows only

Excel:

$ fuefit --excelrun ## Windows & OS X only

Python-code:

import pandas as pd
from fuefit import model, processor

input_model = mdl = model.base_model()
input_model.update({...})                                   ## See "Python Usage" below.
input_model['engine_points'] = pd.read_csv('measured.csv')  ## Can also read Excel, matlab, ...
mdl = model.validate_model(mdl, additional_props)

output_model = processor.run(input_model)

print(model.resolve_jsonpointer(output_model, '/engine/fc_map_params'))
print(output_model['fitted_eng_points'])

Tip

The commands beginning with $, above, imply a Unix like operating system with a POSIX shell (Linux, OS X). Although the commands are simple and easy to translate , it would be worthwile to install Cygwin to get the same environment on Windows. If you choose to do that, include also the following packages in the Cygwin’s installation wizard:

* git, git-completion
* make, zip, unzip, bzip2
* openssh, curl, wget

Tip

To install python, you can try the free (as in beer) distribution Anaconda for Windows and OS X, or the totally free WinPython distribution, but only for Windows:

• For Anaconda you may need to install project’s dependencies manually (see file(setup.py)) using command(conda).

• The most recent version of WinPython (python-3.4) although it has just changed maintainer, it remains a higly active project, and it can even compile native libraries using an installations of Visual Studio, if available (required for instance when upgrading numpy/scipy, pandas or matplotlib with command(pip)).

  You must also Register your WinPython installation and add your installation into envvar(PATH) (see doc(faq)). To register it, go to Start menu --> All Programs --> WinPython --> WinPython ControlPanel, and then Options --> Register Distribution .

Install

Current x.x.x runs on Python-3.3+ and is distributed on Wheels.

You can install (or upgrade) the project from the PyPi repo using the “standard” way with command(pip).

$ pip install fuefit                                        ## Use `pip3` if both python-2 & 3 in PATH.

Check that installation has worked:

$ fuefit --version
0.0.3-beta.2

You may upgrade all dependencies to their latest version with option(--upgrade) (or option(-U) equivalently) but then the build might take some considerable time to finish.

To install it for different Python versions, repeat step 3 for every required version.

Particularly for the latest WinPython environments (Windows / OS X) you can install dependencies with:

$ pip install -r WinPython_requirements.txt -U .

The previous command install dependencies in the system’s folders. If you want to avoid that (because, for instance, you do not have admin-rights), but you do not want to use a virtualenv, you can install dependencies inside the project-folder with this command:

$ python setup.py install                       ## Use `python3` if you have installed both python-2 & 3.

The previous command install just the latest version of the project. If you wish to link the project’s sources with your python environment, install the project in development mode:

$ python setup.py develop

Usage

Excel usage

Attention!

Excel-integration requires Python 3 and Windows or OS X!

In Windows and OS X you may utilize the excellent xlwings library to use Excel files for providing input and output to the processor.

To create the necessary template-files in your current-directory you should enter:

$ fuefit --excel

You could type instead fuefit --excel {file_path} to specify a different destination path.

In windows/OS X you can type fuefit --excelrun and the files will be created in your home-directory and the excel will open them in one-shot.

All the above commands creates two files:

file(fuefit_excel_runner.xlsm)

The python-enabled excel-file where input and output data are written, as seen in the screenshot below:

After opening it the first tie, enable the macros on the workbook, select the python-code at the left and click the Run Selection as Pyhon button; one sheet per vehicle should be created.

The excel-file contains additionally appropriate VBA modules allowing you to invoke Python code present in selected cells with a click of a button, and python-functions declared in the python-script, below, using the mypy namespace.

To add more input-columns, you need to set as column Headers the json-pointers path of the desired model item (see Python usage below,).

file(fuefit_excel_runner{#}.py)

Python functions used by the above xls-file for running a batch of experiments.

The particular functions included reads multiple vehicles from the input table with various vehicle characteristics and/or experiment parameters, and then it adds a new worksheet containing the cycle-run of each vehicle . Of course you can edit it to further fit your needs.

Note

You may reverse the procedure described above and run the python-script instead:

$ python fuefit_excel_runner.py

The script will open the excel-file, run the experiments and add the new sheets, but in case any errors occur, this time you can debug them, if you had executed the script through LiClipse, or IPython!

Some general notes regarding the python-code in excel-cells:

• The VBA xlwings module contains the code from the respective library; do not edit, but you may replace it with a latest version.

• You can read & modify the VBA xlwings_ext module with code that will run on each invocation to import libraries such as ‘numpy’ and ‘pandas’, or pre-define utility python functions.

• The name of the python-module to import is automatically calculated from the name of the Excel-file, and it must be valid as a python module-name. Therefore do not use non-alphanumeric characters such as spaces(` ), dashes(-) and dots(.`) on the Excel-file.

• Double-quotes(”) do not work for denoting python-strings in the cells; use single-quotes(’) instead.

• You cannot enter multiline or indentated python-code such as functions and/or `if-then-else expressions; move such code into the python-file.

• There are two pre-defined python variables on each cell, cr and cc, refering to “cell_row” and “cell_column” coordinates of the cell, respectively. For instance, to use the right-side column as a poor-man’s debugging aid, you may use this statement in a cell:

  Range((cr, cc+1)).value = 'Some string or number'

• On errors, the log-file is written in file({userdir}/AppData/Roaming/Microsoft/Excel/XLSTART/xlwings_log.txt) for as long as the message-box is visible, and it is deleted automatically after you click ‘ok’!

• Read http://docs.xlwings.org/quickstart.html

Tip

You can permanently enable your Excel installation to support xlwings by copying the VBA modules of the demo-excel file xlwings and xlwings-ext into your file(PERSONAL.XLSB) workbook, as explaine here: http://office.microsoft.com/en-001/excel-help/copy-your-macros-to-a-personal-macro-workbook-HA102174076.aspx.

You can even add a new Ribbon-button to execute the selected cells as python-code. Set this new button to invoke the RunSelectionAsPython() VBA function.

If you do the above, remember that VBA-code in your personal-workbook takes precedance over any code present in your currently open workbook.

Cmd-line usage

fuefit -v

-I fuefit/test/FuelFit.xlsx sheetname+=0 header@=None names:=’[“p”,”rpm”,”fc”]’ -I fuefit/test/engine.csv file_frmt=SERIES model_path=/engine header@=None -m /engine/fuel=petrol -O ~t1.csv model_path=/engine_points index?=false -O ~t2.csv model_path=/engine_map index?=false -O ~t.csv model_path= -m /params/plot_maps@=True

Python usage

Example code:

>> from fuefit import model, processor

>> input_model = model.base_model()
>> input_model.update({
    "engine": {
        "fuel": "diesel",
        "p_max": 95,
        "n_idle": 850,
        "n_rated": 6500,
        "stroke": 94.2,
        "capacity": 2000,
        "bore": null,
        "cylinders": null,
    }
})

>> model.validate_model(input_model)

>> output_model = processor.run(input_model)

>> print(output_model['engine'])
>> print(output_model['fitted_eng_maps'])

For information on the model-data, check the schema:

>> print(fuefit.model.model_schema())

You can always check the Test-cases and the mod(fuefit.cmdline) for sample code. You explore documentation in Html by serving it with a web-server:

Contribute

[TBD]

Development team

• Author:

  • Kostis Anagnostopoulos

• Contributing Authors:

  • Giorgos Fontaras for the physics, policy and admin support.

Footnotes

[1]

Bastiaan Zuurendonk, Maarten Steinbuch(2005): “Advanced Fuel Consumption and Emission Modeling using Willans line scaling techniques for engines”, Technische Universiteit Eindhoven, 2005, Department Mechanical Engineering, Dynamics and Control Technology Group, http://alexandria.tue.nl/repository/books/612441.pdf