Since Smath with units is out of the beta stage, I thought I would post these two problems/suggestions here:

First, please see the simple calculation in the screenshot below:



The results are in ksi*m^3. It would be great if there was some way to specify default units in Smath since I almost never use metric units, which would be the case for most engineers in the USA.

Second, when I attempt to change the units to lb*in (which is the desired unit in this case) I get the following result:



This result is unusable. Smath should allow the user to input the desired units (as long as it is consistent with the operations performed) and then recalculate the result based on the desired units.

Anyway, these improvements would be very welcome. The second improvement is far and away the most important because, as it stands now, I cannot use units in Smath because of this limitation.

You have not specified ksi unit. You should change the line "1*ksi:=1000*psi" to "ksi:=1000*psi".

Wrote

You have not specified ksi unit. You should change the line "1*ksi:=1000*psi" to "ksi:=1000*psi".

Andrey,

Thank you for pointing that out. Please see updated screen shots below. The screen shots still show the need for the improvements mentioned above. The default unit is joules (a metric unit) and attempting to change that unit to lb*in still produces an unusable result.



and results after attempting to change unit to lb*in :

Will,
you are confusing mass units with force units.
Mass is a scalar, Force is a vector, and express completely different things

N is a force and in US units converts to lbf (pound force)
kg is a mass and in US units converts to lb (pound mass)

SMath is perfectly consistent with the units, fortunately, and by the way Mathcad behaves the same way.
Since you are dealing with a torque or bending moment, which in SI units is N m, (dimensionally equivalent to J, but physically different meaning), in your case you have to convert N m to lbf in, and not to lb in.
I tried in SMath and it works.
Of course I agree it would be nice to add an option to force default units in the results, but so far you'll need an additional manual work to express results in your archaic units :d .

(just kidding, don't want to start a US&UK vs Europe Flame)

Wrote

you are confusing mass units with force units.

Ah, you are right! I did confuse them! In actual practice, "lb" is usually used to refer to force, but this is ambiguous, which is a fact I should have remembered. Thanks for setting me straight. Please see corrected screenshot below:

Wrote

Of course I agree it would be nice to add an option to force default units in the results,

Yeah, it still would be great if the user could choose his own default units.

First time user to SMATH and i don't mean to be digging up old posts, but there is not currently a way to set default units in smath?

Thanks for developing this program.