3
votes
2answers
93 views

Detecting operator Set in Assumptions

Here is a typical issue: Simplify[x + y, x = y] produces 2 True. Is there a way to detect operator ...
3
votes
1answer
659 views

Is the source code available for examples in the “Mathematica Cookbook” by Sal Mangano?

I looked around a bit and didn't seem to find it. Not as obvious as Wrox books make it, for example. I came across a pdf of the book online [I paid for the paperback] but pasting the code from the ...
3
votes
1answer
428 views

Mathematica - set end-of-line characters when importing

I have a plain text file of tab-separated values that was created on a Windows machine. I want to import it into Mathematica on a Mac. ...
3
votes
3answers
378 views

How to find Image Size of a control object?

I want to find the ImageSize or at least dimensions of any control object irrespective of it being an image or an any other control such as ...
3
votes
1answer
941 views

Solve pair of recurrence relations

[Corrected equations and added simple example] Can you solve a system of (loosely) coupled recurrence relations like this in Mathematica somehow? ...
3
votes
3answers
223 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 ...
3
votes
1answer
107 views

Force ellipsis to print an end of an expression

For pedantic reasons I want to display an infinite sum of fractions in fractional form (i.e. as 1/x not as x^(-1)) with an ellipsis at the end of the expression. I have tried a number of ways and ...
3
votes
1answer
1k views

can mathematica plot graph/visualize rotation matrices

just wondering is there any example online that show plotting of 3d rotation matrices like in the picture below (source)
3
votes
1answer
348 views

How to improve this dynamic progress bar code

I created this progress bar to use in my codes: ...
3
votes
1answer
982 views

stationary distribution of a transition matrix

How can I solve the stationary distribution of a finite Markov Chain? In other words, how can I estimate the eigenvectors of a transition matrix?
3
votes
1answer
629 views

Are there any openCL test suites?

I have a new ATI gpu that I have been trying on 3 different distributed computing projects. I get errors on each work unit. The errors indicate No Protocol which could be caused by a bad environment ...
3
votes
2answers
252 views

Using the elements of a subset in a Do loop

I would like to use the elements of Subsets in a Do loop. I have: ...
3
votes
1answer
216 views

Pattern matching a multivariate derivative

I can extract the parameters of a single variable derivative with the rule D[f[x], x] /. Derivative[order_][fcn_][variable_] -> {order, fcn, variable} ...
3
votes
2answers
749 views

X label in GraphicsColumn is cut off

I'm trying to use GraphicsColumn to plot two curves with very different ranges. for example, ...
3
votes
4answers
2k views

how to plot $x=0$ and $y=0$

I tried to plot plane $x = 0$ and $y=0$ with Plot3D[x = 0, {x, -4, 4}, {y, -4, 4}] but it seems that it didn't work out. How can I plot the above planes? Also ...
3
votes
1answer
249 views

LocatorPane, Dynamic and deleting locators

Compare the following two code snippets : Version 1 ...
3
votes
3answers
466 views

How can I suppress Print in parallel evaluation?

When using a function that includes Print statements, one can suppress the output by ...
3
votes
3answers
656 views

Problem with Union and Intersection

Consider the following: list={{a,b,c},{c,d,e},{d,e,f},...{x_,y_,z_}}; I would like to apply Union on the elements of the list ...
3
votes
3answers
317 views

Combining heads of lists so that you can create a nested list from two sublists

I have a list such as list = {1,4,3,4,6,3,1,2,3,4 ... } and a range, say, range = Range[20000]. I want to obtain the following ...
3
votes
1answer
306 views

n-fold symbolic integral in Mathematica

I am trying to compute symbolically a n-fold integral (n is a parameter of a function) over, say, the cube [0,a]^n. My code looks like this ...
3
votes
2answers
2k views

Plot Indefinite integral

I'm having a hard time to find a solution to a numerical limitation on mathematica: ...
3
votes
7answers
970 views

Defining an integer-valued function on an integer domain

This should be an easy question! I want to define a function with domain = the 12 integers {1,12}, with the values f[1]=31, ...
3
votes
3answers
2k views

How to change step size of ListPlot

The command ListPlot will plot lists with a unit step. Is there any way to change the step size of this?
2
votes
0answers
63 views

Front End does not respond to keys (version 10.2, Linux)

I was often complaining about the front end performance under Linux, but it seems I could pin down a very critical issue. I made a screen-cast that shows how to reproduce the issue Screen-cast on ...
2
votes
1answer
85 views

Memory usage optimization for a large Association/SparseArray

Reformulating my question in simpler terms. Take two lists list1 = RandomInteger[{1, 100000000}, 25000000]; list2 = RandomReal[{1, 10}, 25000000]; Make an ...
2
votes
1answer
60 views

Why isn't Table iterator value inserted in failed NIntegrate arguments?

Consider this simplest example: Table[{z, NIntegrate[f[x], {x, 0, z}]}, {z, {1}}] Here f is not defined, so ...
2
votes
0answers
92 views

Creating a nonlinear phase portrait

I am putting all of my code in one block for easy copy and paste. ...
2
votes
1answer
123 views

NDSolve for axisymmetric problem

I would like to solve an axisymmetric Poisson equation on a disk with FEM. The code for Cartesian coordinates works fine: ...
2
votes
1answer
96 views

simplifying integrals for multiple exponentials

This is somewhat related to this question, but applied to products of Exp[]. For example, I have a symbolic expression containing terms like $Exp[\int_0^1 ...
2
votes
2answers
196 views

How to change the form $A\cos \omega t + B\sin \omega t$ into the form $\sqrt{A^2+B^2}\cos(\omega t-\phi)$ [duplicate]

I'm preparing notes for teaching next week's class in differential equations. My hand calculation solution of $$y''+192y=0, y(0)=1/6, y'(0)=-1$$ is $$y=\frac16\cos 8\sqrt3 t-\frac{\sqrt3}{24}\sin ...
2
votes
2answers
110 views

Math diacritics go missing when exporting graphics [duplicate]

Take this example plot: plot = Plot[x, {x, -1, 1}, Frame -> True, FrameLabel -> {"x", "\!\(\*OverscriptBox[\(x\), \(_\)]\)"}] When I export it to PDF, ...
2
votes
1answer
78 views

Export a Pyramid to VRML format

How do you export a Pyramid to vrml format in Mathematica ? I have been trying to do this the following way ...
2
votes
3answers
335 views

Creating a fast random array generator

I want to create N x N array of random numbers. (N is an integer). The constraints are, each element should be between 0 to l(integer) ( here 0<= l <= N) and the sum of elements in each row ...
2
votes
1answer
264 views

LayeredGraphPlot Vertex Spacing / Edge Length

For anyone who has used LayeredGraphPlot (Mma v9), you have probably seen that the vertex spacing is consistent throughout, that vertices have the same minimum unit ...
2
votes
2answers
132 views

Generating a permutation of elements in chunks

Is there a way for me to generate a list of permutations in "chunks" such that I needn't store everything on RAM all at once? Consider that (WARNING: DO NOT RUN! --- Will generate a list with 13! = ...
2
votes
2answers
507 views

Generate nonoverlapping random circles [duplicate]

I want to distribute n circles unformly in an area(e.g. free plannar space). The circles could touch each other but cannot overlap. ...
2
votes
3answers
316 views

Calculate pixel intensity in two regions

I am just beginning to learn about image processing. I would like to know 1) How to show an original image with a visible mask of an arbitrary shape? 2) how to calculate the pixel intensities in the ...
2
votes
4answers
150 views

Frontend: Adding cell-type choices to the “Choose how to enter input” drop-down [duplicate]

In most of the notebooks I work in, I find myself using 2 or three cell-types almost exclusively (typically regular input, and some subset of section/subsection/chapter). A minor annoyance I run into ...
2
votes
2answers
218 views

Solving a system of nonlinear equations 2

Regarding this question: Solving a system of nonlinear equations When I try to solve the same system (with the code proposed in Daniel Lichtblau's answer) with different Right Hand Side values, ...
2
votes
4answers
183 views

How to use the same PlotRange and the same PlotLabel size for a sequence of Graphics?

I wish to use ListAnimate to show a sequence of plots with different plot ranges and differently sized plot lables, all unknown in advance, in a way that keeps the ...
2
votes
0answers
91 views

Lat-lon contour plots using geographic projections

I need to create contour plots of (lat,lon) quantities projected on geographic regions using different projections. Usually considering the entire world or hemispheres. Coastlines need to be present ...
2
votes
2answers
251 views

How do I feed data points into an equation to solve NUMERICALLY?

I start with this equation and solve it numerically for $z(x,y)$ in the range $1 < x < 5$ and $1 < y < 5$: $$ \frac{3}{xyz} - 2x - 3y - 5z = 0 $$ Then using the data points of $z$ above, ...
2
votes
1answer
174 views

Finding the minimum of a function

I asked this question Mark Minimum Value in DensityPlot. Another question has come up, or better said, a task: Find the minimum of a function. I haven't been able to write the needed code for that, ...
2
votes
1answer
149 views

ListPlot with conditions

I have a data file containing the position of about $10^5$ stars of a spiral galaxy. Here is the plot and this is the corresponding code ...
2
votes
2answers
424 views

How do I exclude the vertical line plotted at a discontinuity?

Condsider function = Tan[1 x] + Tan[2 x] Plot[function, {x, 0, 1.5}] It has a strong discontinuity around 0.8. The problem is , if I want to find ...
2
votes
1answer
306 views

How to enter chemical equations?

When I want to take chemistry notes and write down a formula such as H_2O or C_2H_5OH it enters "Math mode" which changes the font size and italicizes the letters. Is there an easy way to properly ...
2
votes
2answers
92 views

Can I change the font of all elements in my barchart with one property?

I have this BarChart: created with this code: ...
2
votes
2answers
240 views

Problem with Poincare section

these are equations for some double oscillators: $x'(t)=p, p'(t)=-x-3y, y'(t)=q, q'(t)=-y-3x$ I would like to plot the Poincare section for collection of $(y,q)$ when $x=0$ and $x'(t)>0$ (or for ...
2
votes
3answers
760 views

Implicitly differentiate an equation, then solve the resulting equation

Suppose I have an extremely tedious equation to differentiate and want mathematica to help do the differentiation and solve. Consider a less tedious equation: $$y (x,z) = sin \left(\frac{1}{x} ...
2
votes
1answer
170 views

Compute symbolic Expectation of a summation

I am required to computed following Expectations : $E[\displaystyle\sum\limits_{i=1}^N \frac{X_{i}}{N}] = \bar{x}_{0}$ & $E[\displaystyle(\sum\limits_{i=1}^N \frac{X_{i}}{N})^2] = ...

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