Services & Resources / Wolfram Forums / MathGroup Archive

MathGroup Archive 2012

[Date Index] [Thread Index] [Author Index]

Search the Archive

Re: Terrible unit trouble in Mathematic 9

  • To: mathgroup at
  • Subject: [mg129172] Re: Terrible unit trouble in Mathematic 9
  • From: Murray Eisenberg <murray at>
  • Date: Wed, 19 Dec 2012 04:59:33 -0500 (EST)
  • Delivered-to:
  • Delivered-to:
  • Delivered-to:
  • Delivered-to:
  • References: <>

Using "unit discovery" via WolframAlpha integration, if you need to, in Mathematica 9:

  UnitConvert[Quantity[55, "Miles"/"Hours"],"Kilometers"/"Seconds"]

InputForm of the output is

  Quantity[484/19685, "Kilometers"/"Seconds"]

but the output of the UnitConvert function displays (more or less) as:

   ----- km/s

Of course, make the input approximate real, or apply N to the result to obtain a decimal answer.

On Dec 18, 2012, at 2:39 AM, tio540s1 at wrote:

> I continue to receive "Unable to interpret unit specification m/s" (for example, but almost anything I attempt returns this message) with input:
> UnitConvert[55 mi/h,"m/s"] or UnitConvert[55 mi/h,m/s] or any other combination of quotes, omitted quotes, etc. Even the prediction/suggestion box, when I execute Quantity[55,"mi/hour"}, after it returns 55 mi/h, if I type in any combination of m/s, "m"/"s", "m/s", etc. into the box that opens when I select "Convert" in the prediction box yields the same "unable to interpret unit specification.
> What the heck????

Murray Eisenberg                                    murray at
Mathematics & Statistics Dept.      
Lederle Graduate Research Tower            phone 413 549-1020 (H)
University of Massachusetts                               413 545-2838 (W)
710 North Pleasant Street                         fax   413 545-1801
Amherst, MA 01003-9305

  • Prev by Date: Re: Programmatically specifying parameters in "Manipulate" command
  • Next by Date: Re: Input alias for Surd not working
  • Previous by thread: Re: Terrible unit trouble in Mathematic 9
  • Next by thread: Re: Terrible unit trouble in Mathematic 9