# User Portlet

Duncan Pettengill
Discussions
Okay, if you specifically want, not just rational numbers, but successively better rational approximations to Sqrt[2], then you could use Table[Rationalize[N[Sqrt[2], n], 0], {n, 1, 20}] To break this down N[Sqrt[2], n] returns a...
To clarify, the presence of certain words in text cells causes input cells in the same notebook to exhibit this behavior.
In response to the large number of questions on this topic on the Wolfram Community, on StackExchange, and through Wolfram Technical Support, we have published a support article describing these changes, and their rationale, at ...
ImageContents returns its results as a [Dataset][1], which is essentially a list of nested associations. To query part of a list, you use the Part[] syntax, and to query part of an association, you can use the name of the key you want to query. ...
Hello Michael. Mathematica comes with the package "Notation", which allows you to define custom syntax rules and symbols. If you put your expression inside the function Symbolize[], you can treat basically any expression as an atomic symbol. ...
I notice one issue: I think the setup isn't quite correct. Symmetry suggests that the B-field in the x-y plane should only be in the z-direction. Given the Biot-Savart law, I get as my integrand (\[Mu]0 mI)/(4 \[Pi]) Cross[{-a...
Hello Hans, in the absence of any other information, functions like ListPlot[] use the index of the list as the x-axis. Ganymede is the 11th element in the list 'moons', and so appears at x=11. In[2] := Length[moons] Out[2] = 182 And...
![A mandrill-pepper hybrid][1] Recently, I was asked to assist somebody with graphing the Fourier transform of an image. The resulting images were neat, and the work reminded me of a really fun application of Fourier transforms: [Hybrid Images][2]...
To give a slightly longer answer, this goes back to the [Prime Number Theorem][1], which asserts that the number of prime numbers less than n (implemented in the Wolfram language as PrimePi[n]) is approximated by the function LogIntegral[n], in...
Okay, not *all* packages have been rolled into Mathematica. A list of those packages that currently still need to be loaded in is available at https://reference.wolfram.com/language/guide/StandardExtraPackages.html VariationalMethods is indeed...