Re: Wolfram | Alpha: Acres per square mile? (oddities)

*To*: mathgroup at smc.vnet.net*Subject*: [mg101201] Re: Wolfram | Alpha: Acres per square mile? (oddities)*From*: pfalloon <pfalloon at gmail.com>*Date*: Fri, 26 Jun 2009 06:53:30 -0400 (EDT)*References*: <h1vm2n$a8q$1@smc.vnet.net>

On Jun 25, 9:12 pm, AES <sieg... at stanford.edu> wrote: > Just out of curiosity (and a current need for info) (and to start > learning about W|A), typed: > > Acres per square mile > > into Wolfram | Alpha. Results came back (had to do a little hand editing > of the following): > > Assuming U.S. acres for "acres" > Use > international acres > commercial acres > Irish acres > Hungarian acres > instead > > Input interpretation: > > acres/mi^2 > > Unit conversions: > > 0.3861 acres per square kilometer > > 6.323 square meters per acre > > 0.1563 hectares per square kilometer > > 0.4047 hectares per square mile > > 0.003861 acres per hectare > > Don't see "640" there anywhere! -- and something seriously wrong with > that first unit conversion? (not to mention all the others) -- or at > least the way it's phrased -- more like 250 acres per square kilometer? > > Went to M7, tried > > Needs["Units`"] > Convert[Acre, Mile^2] > > Mile^2/640 > > Went to Units Tutorial: Seems odd to see "Centimeter", "Meter", > "Micron", "Mile", and a bunch of arcane units listed there -- but NOT > "Kilometer"??? ("Gram" and "Kilogram" are in there). W|A is interpreting your input as the dimensionless unit "acres/ miles^2", which isn't terribly helpful. To get the value of the ratio the following seem to work: "convert one square mile to acres" "1 square mile / 1 acre" P.S. You may have already done so, but you can/should submit this kind of comment/suggestion in the "send us feedback" field at the bottom of W|A page.