Exponention operator as a variable in MathCad 13

[corus]

Why won't MathCad 13 let you use a variable as an exponent?

For instance when
k=2
d=10m

the expression d^k gives an error saying the exponention operator requires a constant value when applied to a value with units. This seemed to work in MathCad 11.


corus

 

[jghrist]

From Mathcad help:

To unit balance an exponent, nth-root, or derivative equation, the units of the result must depend only on the units of the arguments, not on the numeric value of the arguments. Explicit (constant) values must be used to calculate the powers of a quantity with units. This means you cannot assign the exponent, radical, or order of the derivative with a function argument, or a variable name defined in the worksheet.

 

[IRstuff]

Otherwise known as SUC(K) Static Unit Checking.

This was introduced in version 12 and has not improved with age. I've been told that PTC is working on some modifications to that.

TTFN

Eng-Tips Policies FAQ731-376

 

[davidbeach]

That's one of the reasons that version 11 is the standard reference version. None since has been quite as well worked out.

 

[corus]

Thanks all. Is it worth skipping version 13 and waiting for version 14?

corus

 

[IRstuff]

version 14 is faster than 13, but still has SUC. If you're not doing ODEs and the like, it's probably not worth the upgrade. 14 does feature a different symbolic engine, i.e., the MuPad engine, instead of the Maple engine in the previous versions.

TTFN

Eng-Tips Policies FAQ731-376