We’re rewarding the question askers & reputations are being recalculated! Read more.

Questions tagged [units]

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

Filter by
Sorted by
Tagged with
37
votes
8answers
4k views

Simpler input for the new unit support

I've been playing with the new unit support in Mathematica 9. It seems very useful, but the syntax is very verbose. Instead of typing: ...
34
votes
2answers
2k 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 ...
16
votes
3answers
920 views

How to convert between various ItemSize/ImageSize units?

How can one convert between the implicit units used by Grid (ems and line height for horizontal and vertical dimensions) and printers points (in ...
17
votes
5answers
2k views

Implementing CGS unit system in Mathematica 9

So I've just installed the trial version of Mathematica 9. The first noticeable feature for me is the new built-in physical units. I used AutomaticUnits package ...
3
votes
2answers
2k 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: ...
30
votes
2answers
720 views

Speed of curated data calls in Version 10

Curated datasets underwent a significant overhaul in version 10, primarily in the way content is delivered in the form of Objects and Entities. Additionally, it appears that this change in content ...
15
votes
2answers
1k views

Where to see all Mathematica units [duplicate]

Is there a tutorial page that have all Mathematica units? I sometimes have hard time figuring out the correct unit spelling when using quantities
19
votes
3answers
1k 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 <...
8
votes
1answer
673 views

Using physical dimensions in Mathematica DSolve

I would like to calculate a system of two differential equations in Mathematica using DSolve, like: ...
29
votes
2answers
647 views

Should 0 * 5ft be 0 or 0ft?

After playing with the new quantity system in Mathematica 9 for a while, I keep stumbling over this issue: 0 * Quantity[1, "Meters"] is not the same as ...
14
votes
4answers
4k views

How to dequantify units in mathematica?

Is there a function which applied to a quantity returns its numerical value so I for instance can fill it into my Predictorfunction?
5
votes
1answer
427 views

Getting all physical units with prefixes

How we can get the list with all physical units and prefixes from WolframAlpha and make symbols from the result to be equal their corresponding quantities like described in this post?
6
votes
1answer
482 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
vote
1answer
217 views

How to set UnitSystem permanently

I would like to set the system of units ($UnitSystem) permanently to "Metric". I know that I can do ...
39
votes
4answers
3k views

Are Mathematica 9 and 10 units really slow?

This generates 75 unitized pairs for a plot that displays physical units: ...
15
votes
1answer
579 views

Unexpected behavior of UnitConvert

When I evaluate this expression: ...
20
votes
1answer
4k views

Is there a “No Units” (i.e., dimensionless) unit?

I would like to be able to call the Quantity function with a null unit so that it returns the original dimensionless value. For example, ...
8
votes
0answers
556 views

Units: Custom-defined units possible? [closed]

Converting between revolutions per minute (RPM) and revolutions per second (RPS) is not straightforward for me in Mathematica. I know that $1\; \text{RPM} = \frac{2\; \times\; \Pi\; \text{Radian}}{\...
8
votes
2answers
669 views

Physical (and other) constants

As Mathematica documentation likes to say, "As of Version 9.0, physical constant functionality is built into the Wolfram Language". After clicking on the ">>", one ...
6
votes
3answers
425 views

Why does this Quantity calculation lose precision?

...
10
votes
2answers
393 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 ...
8
votes
1answer
307 views

Change units in PlanetData[“Earth”, “Diameter”] from miles to km

When I enter AstronomicalData["Earth", "Radius"] I get Quantity[6.3674447*10^6, "Meters"] I would have preferred kilometers, ...
5
votes
2answers
214 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): ...
4
votes
2answers
1k 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 ...
3
votes
3answers
299 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/...
7
votes
1answer
293 views

Quantity and Trig functions

I have a bunch of data to which I've assigned units using Quantity, including some angular measurements in degrees. I'd like to be able to use these measurements ...
6
votes
3answers
380 views

Can't force UnitConvert to be evaluated in Plot

I'm trying to use new units support in Mathematica 9. When I Plot Quantity functions everything is OK. ...
5
votes
1answer
323 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: ...
4
votes
1answer
3k 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 ...
4
votes
0answers
107 views

Inequality involving Quantity stays unevaluated

Bug introduced in 10.1 and solved in 11.1 An expression like this one a < x < b is represented as Less[a, x, b] ...
3
votes
1answer
138 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"?
2
votes
1answer
194 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 ...
0
votes
1answer
116 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 ...