Dear Edward,
Thanks a lot! This has solved most of my problems - there was a second
one (maxima did insist in using other units than I am used to, which was
solved by setunits([kilometer,second]).
For the last problem I had to solve I have a question, though:
Do you - or does anybody else in this list - know if there is a good
reason why unit.mac cannot automatically do a
assume(kilometer>0,farad>0,ohm>0);
and so on? Without this assumption
sqrt((2*ohm)^2)
results in:
2|ohm|
instead of:
2 ohm
since maxima has no way of determining if 2*ohm is positive or negative.
Not defining units to be positive or negative sounds right at the first
sight. But it prevents from optimizing things like (a*|ohm|*a*ohm)/(a*|
ohm|+a*ohm) and tends to provoke errors when a is assigned a value.
---
Just for interest: Both the source of unit.mac and the manual seem to
indicate that
metricexpandall(3);
should enable me to use units like picrofarad or femtogram but in
reality doesn't seem to define these units.
Does anybody know if I got something wrong or if I found a bug?
Thanks again,
and
Kind regards,
Gunter.
Am Mittwoch, den 23.01.2013, 11:11 -0800 schrieb Edward A Romana:
> ~~
>
> Gunter
>
> First load the units program
>
> (%i1) load("C:/~path/bsiunits.mac")$
> [meter,kilogram,second,ampere,kelvin,mol,candela]
> "Type units_help() to display units help"
>
> For your expression %e^(numerical_value * unit_dimensionless_group )
> then
>
> (%i2) %e^(1*second/(1*farad*1*ohm));
> (%o2) %e
>
> Also, the style for units has: the unit name is always singular. The
> nice single letter unit symbols are not used in units,
> does 'm' stand for mass or meters etc. Unit names are somewhat
> verbose.
>
>
>
>
> ear.
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