Re: Unit conversion of a list of quantities
- To: mathgroup at smc.vnet.net
- Subject: [mg131974] Re: Unit conversion of a list of quantities
- From: Itai Seggev <itais at wolfram.com>
- Date: Fri, 8 Nov 2013 16:22:44 -0500 (EST)
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- References: <20131107052837.122DC6A56@smc.vnet.net>
Not possible. UnitConvert has attribute Listable and therefore must work over
lists the same way as scalars. Also, it works for me
In[5]:= fdep/mass
Out[5]= {1.1264*10^-12 J/g,2.672*10^-13 J/g,2.672*10^-13 J/g}
In[6]:= UnitConvert[%, "Grays"]
Out[6]= {1.1264*10^-9 Gy,2.672*10^-10 Gy,2.672*10^-10 Gy}
If it's not working for you, perhaps you somehow entered the unit so that your
"g" isn't Grams but some other unit, like g-force. Look at mass//InputForm
It should be using "Grams":
In[9]:= mass // InputForm
Out[9]//InputForm=
{Quantity[0.043937500000000004, "Grams"], Quantity[0.06987, "Grams"],
Quantity[0.02329, "Grams"]}
On Thu, Nov 07, 2013 at 07:27:51AM +0100, mariusz sapinski wrote:
> Hi Itai,
> Many thanks for your suggestion. For a single quantity it works. It
> does not do anything for a list of quantities (see screenshot).
> Could it be that UnitConvert cannt take a list as an argument?
> Cheers,
> Mariusz
>
> On Thu, Nov 7, 2013 at 6:39 AM, Itai Seggev <[1]itais at wolfram.com>
> wrote:
>
> On Thu, Nov 07, 2013 at 12:28:37AM -0500, mariusz sapinski wrote:
> > I have the following lists:
> > Edep = {4.9491200000000017`*^-14 Joules,
> > 1.8669264000000004`*^-14 Joules, 6.223088000000001`*^-15 Joules}
> > mass = {0.043937500000000004` g, 0.06987` g, 0.02329` g}
> >
> > I want to calculate dose:
> > dose = Edep/mass
> >
> > I get another list (of Quantities):
> >
> > {(1.1264*10^-12 Joules)/g, (2.672*10^-13 Joules)/g, (
> > 2.672*10^-13 Joules)/g}
> >
> > OK, but I want to have Grays, ie. Joules/kg:
> >
> > UnitConvert[dose, "Joules/kg"]
> >
> > Unfortunately output is not what I want:
> > {UnitConvert[(1.1264*10^-12 Joules)/g, "Joules/kg"],
> > UnitConvert[(2.672*10^-13 Joules)/g, "Joules/kg"],
> > UnitConvert[(2.672*10^-13 Joules)/g, "Joules/kg"]}
> >
> >
> > How to get Mathematica to convert J/g to J/kg?
> > Mathematica 9.0.1 on linux.
> >
> > Regards, Mariusz
> Why not just convert to Grays?
> In[23]:= Quantity[5, "Joules"/"Grams"];
> In[24]:= UnitConvert[%, "Grays"]
> Out[24]= Quantity[5000, "Grays"]
> If you wish to convert to J/Kg, you must use correct syntax:
> In[25]:= UnitConvert[%, "Joules"/"Kilograms"]
> Out[25]= Quantity[5000, ("Joules")/("Kilograms")]
> --
> Itai Seggev
> Mathematica Algorithms R&D
> 217-398-0700
>
> References
>
> 1. mailto:itais at wolfram.com
--
Itai Seggev
Mathematica Algorithms R&D
217-398-0700
- References:
- Unit conversion of a list of quantities
- From: mariusz sapinski <mariusz.sapinski@gmail.com>
- Unit conversion of a list of quantities