missing units in value expression parser

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bernd
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Re: missing units in value expression parser

Post by bernd »

uwestoehr wrote: Mon Jun 24, 2019 11:33 pm
bernd wrote: Mon Jun 24, 2019 3:09 pm In the regard of this n, m, c, d, k ... this seams reasonable make this available to all units without the need to define it for every unit. But needs someone with knowledge of the internals of FreeCAD Unit system who has time and interest to implement this.
I know. my spare time is too limited and I already promised too many things I could not deliver.
haha same problem here. I stopped promising to much ... :D :mrgreen:
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bernd
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Re: missing units in value expression parser

Post by bernd »

Just had a look, unit Volt is fully implemented. It is called electric potential.

- https://github.com/FreeCAD/FreeCAD/blob ... nit.h#L111
- https://github.com/FreeCAD/FreeCAD/blob ... t.cpp#L440
- https://github.com/FreeCAD/FreeCAD/blob ... t.cpp#L477
- https://github.com/FreeCAD/FreeCAD/blob ... it.py#L354
- https://github.com/FreeCAD/FreeCAD/blob ... it.py#L320

It is just not implemented as a material constant in material editor. AFAIK electric is not a material constant. Am I wrong?
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bernd
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Re: missing units in value expression parser

Post by bernd »

bernd wrote: Wed Jun 26, 2019 8:49 pm It is just not implemented as a material constant in material editor. AFAIK electric is not a material constant. Am I wrong?
But for sure the electrical conductivity is a material constant https://en.wikipedia.org/wiki/Electrica ... nductivity and not implemented in FreeCAD unit system. Would this be needed?
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bernd
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Re: missing units in value expression parser

Post by bernd »

but to be honest I am a concrete guy ... I know how to put in a light bulb but my knowledge does not go much further :oops:
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bernd
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Re: missing units in value expression parser

Post by bernd »

FEM has a constraint electrostatic potential which uses Volt and you are right since it is not implemented it is not possible to use mV.
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uwestoehr
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Re: missing units in value expression parser

Post by uwestoehr »

bernd wrote: Wed Jun 26, 2019 8:49 pm Just had a look, unit Volt is fully implemented. It is called electric potential.
It does not work for me because the parser doesn't recognize it. I had a loot and to me it seems it is missing in 3 files:
https://forum.freecadweb.org/viewtopic. ... 34#p315856
Jee-Bee
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Re: missing units in value expression parser

Post by Jee-Bee »

bernd wrote: Wed Jun 26, 2019 9:01 pm electrical conductivity
Here some more/ others : https://www.electrical4u.com/electrical ... materials/
  • Resistivity
  • Conductivity
  • Temperature coefficient of Resistance
  • Permittivity
  • Thermoelectricity
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