Questions about using, converting, or interpreting units of measurement in Mathematica.

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4
votes
2answers
488 views

Using units and piecewise functions in Integrate

For simple cases, Quantities appear to be handled well by Integrate: ...
4
votes
1answer
172 views

NumberForm and units

NumberForm can be used to print Quantities to a specified precision. For example, x=Quantity[5.123456789,"Meters"]; 5.12346 m Print[NumberForm[x,{4,2}]] 5.12 m ...
4
votes
1answer
70 views

Atom weight in SI units

In chemistry is very common to use the units grams/mol for the atomic weigth, so the mass of one atom (of Tin, for example) is calculated as : massOfOneAtom = (0.11871 (Kg/mol))/(AvogadroConstant (1/...
4
votes
1answer
529 views

Problem in units convertion when multipliying Boltzmann constant and a temperature

When define the temperature of a variable in Celsius, Mathematica 9.0 does not calculate the right answer when multiplying by boltzmann constant. Example: ...
4
votes
1answer
53 views

MixedRadix rounds incorrectly

You can Round Quantitys. For example, how many inches are in a meter? ...
4
votes
0answers
74 views

Inequality involving Quantity stays unevaluated

Bug introduced in V10.1 and presisting through V10.4 An expression like this one a < x < b is represented as ...
3
votes
3answers
260 views

How to extract numeric value?

Considering two situations: I have a string "F2.5" and Quantity["2.3s"]. How can the numeric value be extracted to have: ...
3
votes
3answers
291 views

How to deal with units in logarithms?

I'm trying to take a formula, take it's integral which yields a formula with logarithms, and then directly plug in values with units and get an answer. However if the units go into any of the ...
3
votes
1answer
2k 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 ...
3
votes
2answers
137 views

Something wrong with the way units are handled in V10

(This applies only to version 10) I obtain these two properties of silicon: a = ElementData[14, "CrustAbundance"] b = ElementData[14, "MeteoriteAbundance"] both ...
3
votes
1answer
1k views

How to get the quantity of Physical constants?

I need to get the quantity of gravitational constant: QuantityMagnitude[GravitationalConstant] why this is not work? Already load the ...
3
votes
1answer
737 views

Unit issues in Mathematica 9

I posted the following on the Google+ group comp.soft-sys.math.mathematica and had no luck with responses. I've done a Google search and, to the best of my ability, ...
3
votes
3answers
260 views

Inputting abbreviated units [duplicate]

Possible Duplicate: Simpler input for the new unit support Is there a way to input abbreviated units directly from the keyboard? One can get a value with abbreviated units through the Wolfram/...
3
votes
1answer
36 views

How to get Quantity to collect like terms?

In Mathematica numerical terms collect when their variables are equal. .2 "SERC" + .7 "SERC" (* 0.9 "SERC" *) However, numerical ...
3
votes
2answers
127 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 ...
3
votes
2answers
1k views

Units, plotting and empty plots

maybe I'm completely newbie but I can't understand the behavior of units and the command plot. I'm doing some easy plotting of the state equation for gasses: ...
3
votes
1answer
104 views

Is there a way to display units in short label?

For example, forQuantityUnit[Quantity[1, "Meters"]], is there a way to display the results as"m" instead of "Meters"?
3
votes
1answer
137 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 ...
3
votes
1answer
261 views

Why cant Mathematica 9 interpret this unit?

I'm using Mathematica 9.0.1. Sorry for using an image, but pasting code messed up the output formatting. I'd like to represent 25 Btu/(hr ft F). All units are spelled correctly as identified in ...
3
votes
1answer
93 views

Mathematica 10.1 doesn't recognize “Events” unit

Today's Wolfram blog post inspired me to play with the TemporalData and MovingMap features, and in the process of doing so, I ...
3
votes
1answer
491 views

Wavelength, wavenumber, energy and frequency in a ruler

I would like to generate set of four axis relating wavelength, wavenumber, energy and frequency in an arbitrary range. Like in this image but without the labels such as "RADAR". The selection of ...
3
votes
1answer
174 views

Choosing the units for plotting

I´m new to using units in Mathematica. I have read other similar posts about this issue but I haven´t found an answer so far. My problem is simple: I want to plot a certain function with a certain ...
3
votes
1answer
168 views

Converting in various currencies

I was just playing around with Mathematica converting some currencies: ...
3
votes
0answers
60 views

Custom units Compatible with Conversions [closed]

I am writing a Mathematica Palette to work with units, and am wondering if anyone knows a way to define new units outside of the standard ones that come with Mathematica 9. I do know of the ...
3
votes
0answers
105 views

How to insert a formula to FormulaData?

Unit Checking Demo In order to throw a unit error,we run the code ...
3
votes
0answers
169 views

Physical constants seems broken in 10.3

For example, if I just enter Quantity["GravitationalConstant"], then the result is this ...
3
votes
0answers
47 views

Unit of output changes when constant quantity is moved over integral

Why do these two expressions give the same result in different units? In: Integrate[ gravitationalAcceleration Quantity[1, "g/m^3"] fluidArea h, {h, 0, height}] ...
3
votes
0answers
47 views

TimeSeriesInsert issue with Quantity expressions

Solved in Mathematica v10.3 This first sample code works as expected: ...
3
votes
0answers
74 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 ...
3
votes
0answers
101 views

Quantities formatting problem

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

How to specify units for ImageSize Option? [duplicate]

I'm trying out making a CDF and I want it to print within the margins of Letter paper. There is an ImageSize option that I would like to set; some plots will be in ...
2
votes
1answer
84 views

Control units of time series data for plot axis labeling [closed]

Using Mathmatica time series data: ...
2
votes
1answer
64 views

Integrate complains about incompatible quantities in integration limits

When I run the following code, Integrate throws ...
2
votes
1answer
234 views

UnitSimplify returns unexpected non-SI unit combination

I am trying to get units working in mathematica in the following expression for diffusion: $D = {K_B T}/{3 \pi \eta L}$ My code is as follows: ...
2
votes
2answers
1k views

Use of own unit abbreviations

I have been using AutomaticUnits in my calculations. In this package all I had to do was to declare the units I wanted e.g. mm, kN, sec, kPa, litres etc. in terms of existing units, and then use them ...
2
votes
1answer
46 views

Get Isotope Data and Electron Mass in Same Units - kg and Kilograms

I'm trying to find the nuclear mass of $^{238}\text{U}$. To do this, I subtract the electron mass from the atomic mass. I'd like to find the final answer in kilograms. I'd also like to use Mathematica'...
2
votes
1answer
117 views

How do I extract units from an expression

I need to take the units off of this expression: (5 Coulomb)/(6 Second) In order to do some unit simplification. Is there any way to do this? I have tried Case, but could not get it to work ...
2
votes
1answer
187 views

Why do I get QuantityUnits`Private`ToQuantity when trying to use units?

I'm unable to use units in mathematica (10.3.1) When I do Quantity[500, "Feet"] + Quantity[50, "Meters"] the answer I get is ...
2
votes
1answer
101 views

Physical quantities to decimal power

How can I get Mathematica to properly simplify physical quantities with dimensions to decimal power, such as $1 \frac{1}{\text{s}^{0.7}}\text{dynes}\text{/(}\text{cm}^2\text{Pa})$ that should simplify ...
2
votes
1answer
64 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 Quantity...
2
votes
1answer
136 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
193 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
102 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
171 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
0answers
52 views

How would one make units work with a variable of unknown magnitude?

So, right now, I am working on setting various quantities up as functions of R. R will be varying later on, so right now I just have it set to the variable radius. It's breaking my dimensional ...
2
votes
0answers
152 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 $4\...
2
votes
0answers
124 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 <...
2
votes
0answers
78 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 ...
2
votes
0answers
80 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
3answers
163 views

Inconsistent units? [closed]

I have reviewed this statement until my eyes hurt; can someone tell me why the units output aren't lb/ft^2? ...