Questions about calculating with units in Mathematica.

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2
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1answer
78 views

How do you get a country's GDP per capita in Euros?

Right now, I'm getting the data in U.S. Dollars and converting it to Euros like this: ...
2
votes
4answers
145 views

Cancelling units in two-argument ArcTan

Consider ArcTan[3, -3] (* out: *) -Pi/4 ArcTan[3 a Sin[t/2], -3 a Sin[t/2]] (* out: *) ArcTan[3 a Sin[t/2], -3 a Sin[t/2]] However, we can fix the ...
2
votes
1answer
46 views

QuantityVariable usage

When I try to run the following code, Mathematica gives me an error message: "Solve was unable to determine the units of quantities that appear in the input." ...
2
votes
1answer
63 views

UnitConvert to Electronvolts converts to Electronvolts/Moles

The question probably is clear from the title. When I want to convert a kinetic energy, that contains the Molar Gas-Constant into Electronvolts I get eV/mol. ...
2
votes
1answer
107 views

Using Manipulate[ ] with physical units

I'm a new user, and am trying to build a simple Boyle's law system in Mathematica. I want to include the units of the values, as I may need to perform some conversions later. If my quantities are a ...
2
votes
1answer
104 views

Converting in various currencies

I was just playing around with Mathematica converting some currencies: ...
2
votes
0answers
22 views

MixedRadix rounds incorrectly

You can Round Quantitys. For example, how many inches are in a meter? ...
2
votes
0answers
31 views

Powers of dimensionless quantities: is this a bug?

Today I came across the following behavior: Quantity[x, "Minutes"/"Minutes"]^-1 (* Quantity[1/x, (1/#1 &)[("Minutes")/("Minutes")]] *) It seems that ...
2
votes
0answers
76 views

Quantities formatting problem

So I've developed this simple code ...
2
votes
0answers
104 views

Is it possible to use Gaussian cgs units in $Mathematica$ computations?

I was trying to do computations in Gaussian cgs units, and of course I failed due to dimensional issues. For instance, $q_1 q_2/r$ cannot be converted to $\mathrm{erg}$ since Gaussian system uses ...
2
votes
0answers
79 views

List of supported units in Mathematica 9 [duplicate]

Is there a list of supported units in Mathematica 9 documentation? I personal haven't found any; even the physical constants (newly supported as units in 9) can only be found in compatibility ...
1
vote
1answer
40 views

Simplify CubeRoot of meter cubes

Why Mathematica doesn't simplify CubeRoot of meter cubes to meters? r = Quantity[10, "Meters"]; v = 4/3 r^3 Pi; CubeRoot[% * 3/4 / Pi] returns ...
1
vote
1answer
145 views

Solving equations with QuantityVariable

I'm trying to understand how to easily solve equations that use QuantityVariable. Why does this fail? ...
1
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1answer
1k views

Plotting with Units

I'm trying to get Mathematica to plot with units, but I'm having some trouble. Below is a minimal example of trying to plot y = x, where ...
1
vote
1answer
76 views

Changed appearance of Quantity expressions in v10.1.0

After installing Mathematica v10.1.0 (in Windows 8.1 x64), I noticed a change in appearance of Quantity expressions. For example under Mathematica v10.1.0: while ...
1
vote
1answer
397 views

Unit of the frequency axis in BodePlot

I have a simple question: What is the unit of the frequency axis in the BodePlot? I searched the documentation, but only found this: The scaling functions can be specified as ...
1
vote
1answer
116 views

Caching data in Mathematica package

Consider the following: m=Quantity[1,"meter"] If I run the package, it will return 1m But when I load the package, the ...
1
vote
1answer
98 views

Extract function parameters from “unevaluated” FormBox

I want to get the abbreviation for a Unit from its full name eg. "Newtons" => "N". Using ...
1
vote
1answer
71 views

AutomaticUnits in WM10

Despite the unit improvement in WM10, I am still a big fan of the AutomaticUnits package, as I find it faster and more elegant to work with. However, it seems to be ...
1
vote
1answer
40 views

UnitConvert of a Quantity whose value is a function of a Quantity

I am having trouble with UnitConvert when the QuantityMagnitude contains an embedded ...
1
vote
1answer
71 views

Unit System documentation

Is there any documentation on what consists of the unit system "SIBase","Imperial", "SI" and ...
1
vote
1answer
93 views

Grouping units more sanely

Would it be possible to get Mathematica to group units more sanely. For example the calculation: ...
1
vote
1answer
34 views

Can I convert a list of units to a different base set?

I have a list of quantities with varying units (a short example list is shown below): ...
1
vote
0answers
75 views

Geodesy without units?

Suppose I'm interested in the latitude of Los Angeles and I do the following: ...
1
vote
0answers
90 views

Insert a Quantity Unit literal in TraditionalForm

Is there a keyboard shortcut for creating something like the result of this: Quantity["Kilograms" * ("Meters")^2 / ("Seconds")^2] After copying the result to a ...
1
vote
0answers
71 views

Will aliasing the Quantity and UnitConvert functions to “in” and “to” create problems?

It seems that there is a lot of interest in enhancing the use of units in Mathematica; various solutions in the name of brevity, correctness, and general utility have been demonstrated. I've begun ...
1
vote
0answers
122 views

How can I say that all quantities need to be positive (and real)? [duplicate]

Can you say at the beginning of a script in Mathematica that you want all the quantities to be positive (and real)? So that in all calculations, only the real values of these quantities will be ...
0
votes
1answer
98 views

AstronomicalData not including units?

I like using mathematica to do my physics homework, and AstronomicalData is useful for that, but it doesn't seem to work properly with units. [the question is, at ...
0
votes
1answer
27 views

UnitConvert bar <-> Pa

I wanted to use the following unit cMax = Quantity[6.8221*^-9, "L/s/bar"]; But when calculating with it, I recognised there is some strange behaviour. So I tried ...
0
votes
1answer
37 views

Working with symbolic values in Quantities [duplicate]

I have the following expression: x Quantity[y, ("Milliwatts"*"Seconds"^2)/"Joules"] If I try to convert this to the SI unit, I would expect to get ...
0
votes
1answer
87 views

Unit conversion is not simplifying units

I'm running into what looks like an error. ...
0
votes
1answer
71 views

NIntegrate with units: unable to determine the units of quanitites that appear in the input

I want to integrate Planck's law of radiation in a certain wavelength intervall with units. I define some constants: ...
0
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0answers
59 views

Plotting Earth's position with units

I'm trying to plot the Earth position with the Sun in the origin. I have two lists like this: ...
0
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0answers
28 views

Why numerical functions can't digest InterpolatingFunction with units?

Answering this question gave me the idea that I must be missing something.. In brief, numerical functions generally 'understand' units: ...
0
votes
0answers
99 views

Meaning of backtick in conjunction with units [duplicate]

In this fragment from an equation solution the backtick is used twice: ...
-1
votes
1answer
99 views

Make Quantity behave reasonable with Degrees Celsius

When using a Quantity with the unit of "DegreesCelsius" multiplication doesn't work as expected. If you have 10 degrees and ...
-1
votes
2answers
127 views

Why won't Mathematica work with quantities or Quantity[]? [closed]

As you can see in the screenshot below, Mathematica is simply not evaluating any quantities. It is simply listing them as I wrote them. Could anybody give me a pointer as to why this may be?