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

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1
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1answer
38 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 ...
1
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1answer
41 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 ...
7
votes
1answer
66 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, ...
6
votes
1answer
74 views

DateListPlot failing on Inflation Adjusted TimeSeries

Ran across this (possible bug) today. Here's historical West Texas Intermediate oil prices: ...
2
votes
1answer
90 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
119 views

Physical constants seems broken in 10.3

For example, if I just enter Quantity["GravitationalConstant"], then the result is this ...
1
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1answer
56 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
votes
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 ...
1
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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 ...
0
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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? ...
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, ...
1
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2answers
96 views

Converting Units in formula

I have the following formula ...
4
votes
1answer
144 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 ...
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
votes
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}] ...
2
votes
1answer
69 views

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

Using Mathmatica time series data: ...
11
votes
1answer
191 views

How can I get curated data to be expressed consistently in SI units?

AstronomicalData objects are consistently in SI units: ...
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 ...
0
votes
1answer
49 views

Enter meter unit with Histogram [closed]

I'm looking at the documentation for Histogram and I am trying the example: ...
0
votes
2answers
129 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? ...
2
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1answer
59 views

Integrate complains about incompatible quantities in integration limits

When I run the following code, Integrate throws ...
1
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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 ...
2
votes
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
103 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
206 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

TimeSeriesInsert issue with Quantity expressions

This first sample code works as expected: ...
0
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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"]
1
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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 ...
5
votes
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. ...
3
votes
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 ...
1
vote
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
votes
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
votes
1answer
48 views

MixedRadix rounds incorrectly

You can Round Quantitys. For example, how many inches are in a meter? ...
3
votes
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
vote
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 ...
5
votes
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): ...
3
votes
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 ...
3
votes
2answers
165 views

Draw and Quantity

I'd like to use Quantity in my graphics, but I can't figure out how to do it even for a very simple Circle. ...
2
votes
1answer
78 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." ...
1
vote
1answer
56 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
58 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 ...
0
votes
1answer
78 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 ...
1
vote
1answer
50 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 ...
4
votes
1answer
126 views

Dimensionless quantities

I must admit that I don't think this problem is really new. However, I haven't found a post dealing exactly with this aspect of the issue. I am doing calculation using Quantities, but I have problems ...
1
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1answer
94 views

Unit System documentation

Is there any documentation on what consists of the unit system "SIBase","Imperial", "SI" and ...
13
votes
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: ...