Top new questions this week:

Using With to scope over pure functions

Consider this example: given an option for a function func as "x" :> (a&), how can one assign different values to a locally inside func? a = False; (* global value of a *) func[opt_] := …

functions evaluation scoping

asked by István Zachar 10 votes answered by Rojo 12 votes

Problem importing a JCAMP-DX mass spectral file

I have some problems importing a JCAMP-DX EI-mass spectral file using Mathematica 9. For example, if I download the mass spectrum of nonacosane in JCAMP format from NIST, …

import chemistry

asked by Tom Wenseleers 8 votes answered by Sjoerd C. de Vries 8 votes

finding anagrams

What I'm trying to find are the 4 letter words in the mathematica dictionary that have the most anagrams and the amount of anagrams these have each. But I can't seem to find all the 4 letter words in …

map

asked by jas 7 votes answered by rcollyer 7 votes

Import an SPSS, SAS, or STATA file into Mathematica

I would like to import the World Value Survey data file into Mathematica, but it's only given in spss, sas or stata formats, which are statistical analysis softwares format I think. I can't get to …

import

asked by su1 6 votes

Where did I go wrong with my implementation of the trapezoidal rule?

One method for doing quadrature, called the trapezoidal rule, improves accuracy by connecting the points on the curve corresponding to the points of subdivision with line segments, forming trapezoidal …

calculus-and-analysis syntax

asked by Tangshutao 6 votes answered by m_goldberg 6 votes

Extract urls from list

If I have a list like list = {"my element 1 http://link.com", "http://link2.com my element 2"} how do I get a list of the links inside each element? Something like StringCases[list, "http" ~~ …

list-manipulation

asked by su1 6 votes answered by Yves Klett 9 votes

Using PatternTest and/or Condition to detect equal list lengths as well as list element formats

On searching Mathematica.SE for information about overloading functions, I came across several threads about PatternTest and Condition, and I understand the basic examples like matching by EvenQ. …

list-manipulation function-construction pattern-matching argument-patterns

asked by acheong87 6 votes answered by RunnyKine 6 votes

Greatest hits from previous weeks:

How to create new "person curve"?

Wolfram|Alpha has a whole collection¹ of parametric curves that create images of famous people. To see them, enter WolframAlpha["person curve"] into a Mathematica notebook, or person curve into …

graphics image-processing algorithm wolfram-alpha-queries

asked by Simon 41 votes answered by Vitaliy Kaurov 14 votes

ShowLegend values

How do I get ShowLegend to put the max and min values that a plot produces. for example, when using ListDensityPlot, with PlotRange->Automatic, the plot can sometimes clip. How do I get …

plotting legending

asked by Andrew Spott 22 votes answered by Jens 29 votes

Can you answer these?

How to improve gesture detection by JLink for the LeapMotion controller

Building on this thread (where I cannot add anything anymore somehow) and with this nice answer I kind of got swipe detection to work, but it is not very responsive. How to improve (in the sense of …

java

asked by Rolf Mertig 3 votes

Texture[] not working properly with Image AlphaChannel

I recently encountered a problem when combining multiple texture layers in an graphics object when the texture comes from an image with alpha channel. Apparently the alpha channel of the image passed …

graphics textures transparency

asked by Wizard 5 votes

Is everything in Mathematica ultimately stored as a rule?

My current understanding about Mathematica is that everything, at the lowest level, ends up as replacement rules. First question: is this true? Second question: does Mathematica "gloss over" these …

functions replacement core-language

asked by George Wolfe 4 votes