All Questions

313 views

Efficient method to generate Tridiagonal 50 by 50 Matrix? [duplicate]

I'm looking to generate a tridiagonal 50x50 matrix, ideally without using loops. Suggestions on most efficient code for this?
254 views

Incorrect result while using SemanticImport for CSV file import

I might use this incorrectly. I want to use a .csv file that (as list) looks like: ...
1k views

Generating random symmetric matrix

Suppose first that I want to generate a matrix whose elements are independent and identically distributed (i.i.d.) with distribution dist. This is easy: ...
227 views

Why can't a string be formed by head String?

Since everything is an expression in Mathematica, why must a string object be formed by "abc" but not by a String[abc] ...
117 views

Determining the range of parameters that yield real values for a certain NIntegrate form

I have specified just one set of $s$ and $g$ values that yields a real value for the NIntegrate below. It is possible that some $s,g$ combination can give rise to ...
155 views

Why does LinearSolve return the transpose of the answer matrix?

I am trying to solve an equation of the form $dv=F\cdot dV$ where $dv$ and $dV$ are matrices derived from the row vectors $dx$, $dy$, $dz$ and $dX$, $dY$, $dZ$ respectively. If it helps, $F$ is the ...
213 views

Solution of differential equation in terms of incomplete gamma function

I need help in solving equation 15 and 16 either manually or in Mathematica to get the solution in terms of the incomplete gamma function. This is what Mathematica tells me. I can't understand ...
363 views

Any packages for vertex enumeration on Mathematica?

My work requires me to enumerate all vertices of a polytope defined by linear inequalities from time to time. And I'm mainly working with _Mathematica 9.0 on Mac OS X 10.9. So I wonder are there any ...
271 views

Generalize WASD Function First Person Viewing

How might I generalize the following WASD question such that it works with any Graphics3D object and includes q and ...
742 views

How would I input this truth table into Mathematica or Wolfram Alpha

I am unsure how to put the negations after a gate or before a gate?
263 views

Accurately distort graphics

I would like to accurately distort this plot of $\sin(x^{1/2})$ (and others like it) so that the wavelengths are evened out (ie - "inverse-square root" it). I should like to do the same to "de-log" ...
314 views

How to test for Indeterminate values?

I need something like this a = 101010/0; If[a == ComplexInfinity, True, False] But if I use ToString, I get what I want. ...
51 views

How to pattern match an association? [duplicate]

I have the following: Clear[a, b]; a = {{1, 2, 3}, {4, 2, 5}, {6, 7, 8}}; b = GroupBy[a, #[[2]] &]; b whose output is: ...
178 views

Change font of formula number in DisplayFormulaNumbered

I am trying to change the font of the formula number in a cell which has style DisplayFormulaNumbered. I can easily change the font of the formula I enter by selecting it and using the format menu. ...
102 views

Compile issues, scoping and order of evaluation

I have a few questions about compiling functions, which I think are all related to scoping and order of evaluation. I will illustrate them by a minimal example of the problem I have. I'm sorry for ...
282 views

How to remove selected wire frames from bounding box in 3D plots?

In 3D plots one can eventually hide the whole bounding box by the use of option Boxed -> False. How to remove only a selected part of the wire frame that ...
94 views

802 views

Histogram with variable bin size [closed]

Suppose I have some dataset,e.g., Histogram[RandomVariate[PoissonDistribution[2], 10000], 10] which gives, $\hspace{2cm}$ How can I change the histogram such ...
A $2\times 2$ linear ODE system can be visualized by StreamPlot in Mathematica. For example: ...