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Units problem (hiding units)

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mar2805

Structural
Dec 21, 2008
372
People hi!
Back from recovery.
I was wondering is there a way that you can somehow hide units from a defined variable?
Plase look at the file attach.
Variable fck has units defined.
Later on in calculation there is a coefficient (should be unitless) that uses fck value.
Is there any way that this coefficient result could be without units?
Now its using fck units and I could write the equation as in units2 file attached.
Any more sophisticated way?
Thanx
 
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The only way is essentially to divide by the units the equation uses.

TTFN
faq731-376
7ofakss

Need help writing a question or understanding a reply? forum1529
 
I was afraid you would say that :)
Thanx anyway :)
 
You have to tell Mathcad in some way that you want the number w/o the unit. If you would have to do using a special command or simpli by dividing by the unit is the same effort and not that bad at all.

BTW, I replied to this thread yesterday with an attachment but that post seems to be gone.
Anybody an idea how and why??
 
One saving grace is that if you wind up with something like

blah*(fck/psi) = desired answer

any new value of fck can be used with whatever units you wind up with, since Mathcad will do the conversion transparently, i.e., you can use fck with Pa, or whatever. This automatically eliminates the multiple copies of empirical equations configured for different unit systems.

TTFN
faq731-376
7ofakss

Need help writing a question or understanding a reply? forum1529
 
Later on in calculation there is a coefficient (should be unitless) that uses fck value.

Except of course, x DOES have units!

The empirical expression as presented in the source document will only be valid as long as all of the factors are given in the correct units. One of Mathcad's strongest features for me is that it makes such empirical factors "transparent", AND it means you can use whatever units are convenient for you.

(Some people are "Grammar Nazis" - I admit that I am one, but I also have a passionate hate of empirical equations which use "dimensional" factors in Codes and Standards!)

 
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