Re: Engineering requests

*To*: mathgroup at smc.vnet.net*Subject*: [mg125420] Re: Engineering requests*From*: Bill Rowe <readnews at sbcglobal.net>*Date*: Tue, 13 Mar 2012 03:05:29 -0500 (EST)*Delivered-to*: l-mathgroup@mail-archive0.wolfram.com

On 3/12/12 at 4:06 AM, Paul.McHale at excelitas.com (McHale, Paul) wrote: >David, >>>Have you explored the Units` package? >I have, but have probably not given it sufficient time. I'm not >sure "automatic" and "natural" would describe the implementation. Another package you might want to look at for using units is the AutomaticUnits package available on Wolfram's web site. It has a few advantages over the standard Units package for working with units. For example, it allows you do something like In[3]:= Exp[.7 ElectronVolt/ BoltzmannConstant (1/(298 Kelvin) - 1/( 398 Kelvin))] Out[3]= 942.91 Note, to make this work as shown, I've modified my copy of the PhysicalConstants package to call out the AutomaticUnits package rather than the standard Units package. But while the AutomaticUnits package will convert diverse units for a common quantity such as energy without your being concerned, it will not automatically simplify units to those you might prefer. That is: In[4]:= 2 Volt/(10. Ampere) Out[4]= 0.2 V A^-1 doesn't out ohms.