Re: Quantity

*To*: mathgroup at smc.vnet.net*Subject*: [mg131730] Re: Quantity*From*: Bill Rowe <readnews at sbcglobal.net>*Date*: Wed, 25 Sep 2013 02:35:45 -0400 (EDT)*Delivered-to*: l-mathgroup@mail-archive0.wolfram.com*Delivered-to*: l-mathgroup@wolfram.com*Delivered-to*: mathgroup-outx@smc.vnet.net*Delivered-to*: mathgroup-newsendx@smc.vnet.net

On 9/24/13 at 4:16 AM, itais at wolfram.com (Itai Seggev) wrote: >On Sun, Sep 22, 2013 at 02:47:41AM -0400, Bill Rowe wrote: >>There does not seem to be a specific set of unit strings. Note that >>doing: >>In[1]:= UnitConvert[Quantity[12., "Feet"], "Meters"] >>Out[1]= 3.6576 m >>returns a result essentially immediately. But doing >>In[2]:= UnitConvert[Quantity[12., "Foot"], "Meters"] >>Out[2]= 3.6576 m >>returns the same result after a small delay. You should see a brief >>message indicating Mathematica is interpreting the units. I believe >>what is happening here is Mathematica is using Wolfram Alpha to >>interpret the unit string which increases the allowable number of >>unit strings significantly and makes it essentially impossible for >>a user to create a list of allowable unit strings. >I'm not sure if you are complaining about or praising the >flexibility of input, Neither. I was simply trying to show why it would be difficult to enumerate a specific list of units Mathematica can utilize. >but you can always see the canonical unit name >by looking at the InputForm. >In[3]:= Quantity[5, "Foot"]//InputForm >Out[3]//InputForm=Quantity[5, "Feet"] True. But this doesn't really answer the original poster's question. Is there a method to create a list of unit strings known to the kernel, i.e., those that would not involve a query to Wolfram Alpha? >You can also turn off internet connectivity in the preferences if >you don't want Quantity to try to interpret units for you by asking >W|A. I am happy with Mathematica asking Wolfram Alpha. That generally makes my life simpler. But I can also see why it might be nice to have a list of unit strings Mathematica will work with without asking Wolfram Alpha.

**Follow-Ups**:**Re: Quantity***From:*Sseziwa Mukasa <mukasa@gmail.com>