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MathCAD 15 - strip variable's units?

thread552-457168

MathCAD 15 - strip variable's units?

MathCAD 15 - strip variable's units?

(OP)
I've run into various situations where it would be useful to just simply strip the units off of a variable, so you are only left with the scalar value.

...or even just using a function to check the units of a variable that is already defined.

I've never been able to find anything, but is there a built-in function or a convention for stripping away the units?

RE: MathCAD 15 - strip variable's units?

Could you define a Pscalar quantity after P and manually strip the units off.

P := 100lbf
Pscalar := P/lbf


...but I can't recall if I have ever solved that problem yet.

RE: MathCAD 15 - strip variable's units?

(OP)
I'd like to come up with a more generic function that can work with any variable and any unit...

I just don't know if it's possible...

CODE --> Pseudocode

TruncU (P) := what units does variable "P" have?

 If units = lbf
Then TruncU (P) = P / lbf
If units = psi
Then TruncU (P) = P / psi
...

RE: MathCAD 15 - strip variable's units?

When I need a variable to be unitless, I've always found it easier to just divide out the units when I make the equation:


You have to track it on your own, but you'd be doing that anyway with your unit stripping function.

RE: MathCAD 15 - strip variable's units?

The only safe way to "strip units" is to divide by the units manually.

As IRstuff says, you can use the "UnitsOf" function, but it divides by the base units. How would a fully automated solution that strips the units of any / all variables know whether you wanted the scalar answer for a 10 kilogram mass (say) to be given as 0.01 (tonnes), 10 (kg), 10000 (g), 22.046 (pounds) or 352.74 (ounces)?

http://julianh72.blogspot.com

RE: MathCAD 15 - strip variable's units?

(OP)
Wow. I never knew "UnitsOf" was an actual function that existed. It's not exactly what I was hoping for, but it's at least a step in the right direction. Might be able to fudge a useful custom function with it. Neat!

RE: MathCAD 15 - strip variable's units?

P:=2500*lbf

P/UnitsOf(P)returns 1.112 X 10^4 regardless of which Unit System is chosen. Seems to be identical with the SIUnitsOf function.

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