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Units-filter
############
:author: Georges Khaznadar <georgesk@debian.org>
:copyright: 2000-2020
:licence: GPL v2+
Units-filter is a basic standalone filter written in C language,
flex and bison. It inputs strings like `"1.5e3 µN.m.s^-1"` (it could
be the time growth ratio of a torque) and outputs the value in
standard SI unit, followed by the physical dimension of this value.
.. code-block::
example:~/src$ echo 1.5e3 µN.m.s^-1 | units-filter
0.0015 2 1 -3 0 0 0 0
example:~/src$
which means : |formula1|
When the input is not successfully parsed, the filter fails with
the exit code `1`.
This filter can be embedded in educational test systems, in order to
analyze a student's answer to a problem of physics or chemistry.
Unit-filter has many features, like:
- prefer usual units, rather than raw SI units
- output LaTeX code
- take precision in account (fit to a given number of significant digits)
Feedback is welcome.
INSTALLATION
============
inside the src/ subdirectory, run "make".
You can try the script `units-test` to see some typical inputs and
outputs.
.. |formula1| image:: formula1.png
:alt: 0.0015 (SI unit) m^2 .kg^{-3}.s
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