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

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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 ...
1
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1answer
37 views

How to correctly use FormulaData

I am exploring some of the functions involving units and formulas, and wondered how to input quantities if the variable has a subscript. This works ...
6
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1answer
72 views

DateListPlot failing on Inflation Adjusted TimeSeries

Ran across this (possible bug) today. Here's historical West Texas Intermediate oil prices: ...
7
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1answer
65 views

Why does the front-end no longer like MixedRadix as an argument for UnitConvert?

I often find MixedRadix very useful for make certain kinds of unit conversions. For example, ...
2
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1answer
88 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 ...
4
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2answers
116 views

What's wrong in “Watt”/(“Centimeters”)^2 [closed]

Why Mathematica returns the following input unevaluated? ...
3
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0answers
117 views

Physical constants seems broken in 10.3

For example, if I just enter Quantity["GravitationalConstant"], then the result is this ...
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1answer
46 views

Differential Equations and Unit Notation

What do I get the Syntax::sntxi: Incomplete expression; more input is needed . error when I try to use the math palette for derivatives? What does the dot in 10. Farad Micro Volt mean? ...
5
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1answer
61 views

Plotting with units — getting the right axes labels

I have a simple example: Plot[UnitConvert[Quantity[x, "DegreesCelsius"], "DegreesFahrenheit"], {x, -25, 300}, AxesLabel -> Automatic] The x-axis has the ...
5
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2answers
139 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): ...
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2answers
122 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 ...
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0answers
55 views

Convert large KML coordinate datasets to UTM [closed]

I was wondering if there are ways to convert massive amounts of KML coordinates into UTM coordinates using Mathematica. Other programs would also be acceptable. Thanks. I have the KML file from ...
3
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1answer
90 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 ...
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1answer
58 views

Electromagnetism units conversion in Mathematica 10 (possible bug)

Is this a bug in Mathematica 10? Why can't I convert Amps/m to Gauss? ...
29
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2answers
1k views

Built-in unit strings recognized by Quantity?

It’s great that Quantity can utilize Wolfram Alpha to interpret unit strings that it doesn’t recognize, but I need my code to work on machines that do not have ...
0
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0answers
29 views

A complete list of quantities in Mathematica 9/10? [duplicate]

Often times when I'm traveling I don't have internet access and cannot reliably use Wolfram Alpha for unit look-up. Additionally, Alpha can always choose to change how it interprets the units I enter, ...
3
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2answers
166 views

Display Quantity in full form

Is there a way to display Quantity[] in full form in the output? I know you could use Quantity[valuse, Unit]//InputForm, but ...
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2answers
96 views
4
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1answer
143 views

Calculating consumed internet data from bitmap of chart

My internet connection has a speed drawn up by the y axes has a scale as KB per second. and the x axes is time elapsed. if the x axes be from 0 to 40 minutes how can I calculate total consumed ...
13
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2answers
2k views

Numerical value of physical constants Mathematica 10

Is there a way to use the physical constants in calculations and have Mathematica 10 figure out the final unit and numerical magnitude? When I try ...
4
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0answers
42 views

Calculations with “Quantities” Run Slow. What am I doing wrong?

This code plots a 1000 point black body radiation curve in 0.7 seconds. ...
2
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0answers
44 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 ...
3
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0answers
46 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}] ...
11
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1answer
176 views

Why is this evaluation halved when adding units?

Why does this strange behavior occur when dealing with units and quantities? ...
6
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2answers
204 views

Is it reasonable to have both TemperatureUnit and TemperatureDifferenceUnit?

When adding the bugs header to the question "Kelvin per Kelvin Difference" I was confused by the fact that I cannot determine for sure whether the described bug is fixed in version 10.2 or not: from ...
11
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1answer
191 views
18
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3answers
652 views

Kelvin per Kelvin Difference

Bug introduced in 9 and partially persists through 10.2 or later The specific bug described in the original question is fixed ("Kelvin" is correctly recognized as ...
13
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1answer
275 views

Possible bug: Quantity[2,“meters”] returns 2 None meters

Bug introduced in version 10 or earlier and fixed in version 10.0.2 I'm using 10.0 for Linux. Trial 1: Quantity[2,"meters"] 2 None meters Trial 2: ...
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1answer
49 views

Enter meter unit with Histogram [closed]

I'm looking at the documentation for Histogram and I am trying the example: ...
0
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2answers
128 views

Converting the units of an equation or expression (how to become 3 times heavier…)

(THIS QUESTION HAD A MAJOR SIMPLIFICATION EDIT) Lets suppose I want to convert the falling body equation, from one set of units to another. I start with: ...
1
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3answers
153 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? ...
1
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1answer
139 views

UnitConvert to Electronvolts returns Electronvolts/Moles [closed]

The question is probably 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
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1answer
59 views
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0answers
26 views

Using Infinity with AutomaticUnits

I am using the AutomaticUnits package in Mathematica 10, and I am writing some unit checking functions. However, I run into a problem when I have an Infinity, since ...
4
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1answer
164 views

LowpassFilter in v10: unit issues?

Bug introduced in 10.0.0 and fixed in 10.1.0 I tried this with a clean start and no documents loaded. Now, evaluating the following on the documentation page for ...
37
votes
4answers
3k views

Are Mathematica 9 and 10 units really slow?

This generates 75 unitized pairs for a plot that displays physical units: ...
2
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1answer
95 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
102 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 ...
3
votes
3answers
205 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: ...
2
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0answers
31 views
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0answers
22 views

QuantityArray display and UnitConvert

In the reference: But if you try (Mathematica 10.1 Windows 8.1 x84): qa = QuantityArray[{2.3, 1.5, 9.0}, "Meters"]
5
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1answer
112 views

How to create fast functions based on units?

Using units is a good means for rapidly developing code, since it provides some error control. Hovewer, using Mathamatica functions containing units appears to be copmutationally inefficient. ...
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0answers
52 views

Using Quantity[] units causes errors in my calculation

I have an interpolation function in which I wish to use actual units. If I perform the calculation normally, it works fine and returns a proper FittedModel. To illustrate my problem, consider the ...
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0answers
47 views

Inequality involving Quantity stays unevaluated

Mathematica 10.1.0, Windows 8.1 x64 An expression like this one a < x < b is represented as Less[a, x, b] while ...
5
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1answer
279 views

UnitConvert works despite wrong dimension - bug or feature?

I am surprised that there are some cases where unit conversion works, even if the input- and output dimensions are clearly different: ...
3
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1answer
48 views

MixedRadix rounds incorrectly

You can Round Quantitys. For example, how many inches are in a meter? ...
3
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0answers
66 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 ...
5
votes
1answer
73 views

How do I perform exact unit conversions with irrational conversion factors?

Suppose I want to express $3h$ in units of $\hbar$ (where $h$ and $\hbar$ are the Planck constant and reduced Planck constant, respectively). By definition, $h = 2\pi\hbar$, but when I attempt this ...
1
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1answer
101 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 ...