0
votes
1answer
508 views

Evaluating FindRoot at different starting points on a grid

I'm trying to evaluate the roots of a complex function at different starting points on a grid using Do[Do[FindRoot[g[z], {z, j + k*I}], {j, 10}], {k, 10}]. However, ...
3
votes
1answer
210 views

Issue with ListConvolve

I am a new Mathematica user, learning the intricacies of functional programming. I have issues withe applying a function over a moving list. My function seems to work and give correct results but it ...
8
votes
4answers
853 views

How make f[{x,y}] evaluate as f[x,y]? [duplicate]

I frequently encounter the situation where I have a function of two real variables defined, e.g.: f[x_, y_] := 9 - x^2 - y^2 But then I need to feed into ...
2
votes
1answer
142 views

Detect Standalone CDF vs Browser Plugin environment [duplicate]

Recently, Wolfram informed me that there's no way to have a Print button in a CDF running within a plugin environment since the plugin does not interact with the operating system. If you have a way to ...
8
votes
1answer
203 views

How can I add a background to a stylesheet?

In version 9 we can set the background to an image, however I'd like to save this into a stylesheet that can be installed.
7
votes
2answers
1k views

How to change coordinates of integration?

Is there some built-in routine, some easier method to change variables of integration, without/before solving the integral? Say I have ...
1
vote
0answers
133 views

Plotting an array of data onto a sphere [duplicate]

See the link to plot at the bottom of this post, it is a function of the spherical coordinates theta and phi. It is generated by MatrixPlot of an Array of data. I would like to plot this onto a sphere ...
5
votes
2answers
729 views

Is there an $n^{\text{th}}$ root function in Mathematica?

Is there a way to find $\sqrt[n]{x}$ with Mathematica beside of x^(1/n) as this is something different, because this is not always the same $$(-1)^{\frac{2}{4}}=i ...
0
votes
0answers
75 views
13
votes
1answer
373 views

What is the confidence limit on this convergence?

When I run this, Product[n^MoebiusMu[n],{n,1,Infinity}] I get $\frac{1}{4 \pi^{2}}$ Over on Math Overflow they are saying it shouldn't happen. So, how do ...
3
votes
3answers
2k views

Multiple assumptions in integral

I want to add two assumptions, so I can get this probability density function to equal 1, though I can't get a solution. ...
3
votes
4answers
904 views

Extract function arguments

Is there a way to extract the arguments of a function? Consider the following example: I have this sum ...
5
votes
4answers
474 views

How to transform Do loop to more efficient codes?

I'm new to Mathematica. Here is my original program: How to rewrite the Do part? ...
11
votes
3answers
655 views

Efficient implementation of a linear complexity measure of binary sequences

For a implementation of testing the quality of random number generators I implemented the NIST test suite in Mathematica based on the nice workbook by Ilja Gerhardt. However I took up the challenge ...
10
votes
4answers
1k views

Coloring Points in a Plot, based on their position in the list

Before I describe the question, I'd like to say that I've seen the excellent answers posted here but have not managed to get them to work for my own data. I have a list of values that I would like to ...
23
votes
2answers
2k views

Making a presentable BarChart

I've been asked to reproduce a bar chart generated in Excel in Mathematica. The original Excel chart looks like this; My Mathematica version looks like this; There are a couple of things wrong ...
14
votes
2answers
621 views

How can I create an advanced grid interface on Mathematica?

Working on a CDF for report creation, I miss having a nice grid interface, where I would have basic operations like being able to sort a columns by clicking on the columns head (ascending and ...
3
votes
1answer
1k views

Increasing the size of numbers in a legend bar

I would like to know how you go about increasing the size of numbers which appear in a legend to make them larger than the default (which is too small for publication purposes). Example: ...
1
vote
1answer
144 views

Output Export in Mathematica

I have a command line that generates lists as output and is running in a loop, so generates, multiple long lists. Each list is to be exported as a .txt file. How can I automate the name generation of ...
2
votes
1answer
271 views

Function definitions in init.m don't work

I can't get any function defined in $UserBaseDirectory/Kernel/init.m to work. For example: ...
7
votes
2answers
319 views

Solving variant of the knapsack/money-changing problem

I'm trying to solve a variant of the knapsack/changing money problem where I have a set of a few numbers and I'm trying to find the linear (integer) combinations of them which are close to a given ...
6
votes
4answers
883 views

ParametricPlot and PlotLegends don't seem to cooperate

Bug introduced in 9.0.1 -- fixed in 10.0.0? I noted that only part of the legend shows up in ParametricPlot using v9's ...
3
votes
2answers
378 views

Find the a factor of an integer which is nearest to another integer

If I know two integers $n$ and $m$ and $m < n$, how can I find two different integers $x$ and $y$ that are nearest to $m$, and satisfy Mod[n,x]==Mod[n,y]==0 ? ...
3
votes
1answer
232 views

Sum of positive terms gives negative answer

Mathematica evaluates Sum[((n - y - 1)*(n - y)^2*n^y)/y!, {y, 0, n - 2}] as -2 e^n n. This should not be a negative value. ...
3
votes
2answers
363 views

Why does the first derivative of a piecewise continuous function have discontinuities?

I have this piecewise continuous function which is also continuously differentiable over time : ...
3
votes
3answers
299 views

How to paint part of DateListPlot?

My graph is about fires (burned area) over 12 years presented in one Date List Log Plot. Because most of fires are in summer (as expected) I would like to highlight that with different background ...
7
votes
1answer
175 views

Can I set 'no-go' values in a Manipulate slider?

Is it possible to easily modify a Manipulate such that the slider automagically skips certain values? For example, say I am plotting an equation that's perfectly ...
13
votes
5answers
1k views

How stretch curly brace on multi-line text?

What's the cell option (or other technique) to use to stretch the curly brace that one typically uses in traditional math to group several displayed equations? Like this: And is there any better ...
0
votes
1answer
489 views

How to use Compile for accelerating matrix multiplications?

I am trying to find the inverse of the matrix $A$ m = n = 500; SeedRandom[123456]; A = RandomReal[10, {m, n}]; iteratively using the following matrix ...
3
votes
1answer
785 views

How do I read a CSV file and remove comments from it

I have very recently started using Mathematica 9.0 Home Edition and am trying to understand it as best I can so please be tolerant ;). I have a file of data (sugar.csv) which contains blood sugar ...
4
votes
1answer
3k views

Transform 3D data into 2D color map like Matlab's surf/imagesc

I have a bunch of 3D data (x, y coordinates and values) which is generated in Matlab and I need to render them in a 2D color map with certain axis ranges. Here are the Matlab code and the generated ...
0
votes
1answer
313 views

NumericQ prevents evaluation at a numerical value sometimes

I set up a symbolic integral, to be evaluated only when some of the symbols have been replaced by numbers. The evaluation after assigning numbers to the symbols is still symbolic for some reason. The ...
4
votes
2answers
284 views

Is it possible to export a live CDF document to PDF in the browser?

I am creating a computable document format (CDF) to embed in an HTML page. I would like to have a button that can be clicked to create/save a PDF of the CDF fromt he browser. The idea is that a person ...
1
vote
1answer
172 views

Colors not showing in Graphics3D

The following code works, except that the colors aren't showing in the output. Wh? I probably made a trivial mistake, but I'm yet unable to find it. ...
17
votes
1answer
3k views

How to solve a non-linear integral equation?

I have a non-linear integral equation that I'd like to solve with Mathematica: $$ \int_{0}^{1} \mathrm{d}x \frac{B(x) v}{(B(x) + B(v))^2} = 1$$ ...
3
votes
1answer
482 views

How to get the determinant and inverse of a large sparse symmetric matrix?

For example, the following is a $12\times 12$ symmetric matrix. Det and Inverse take too much time and don't even work on my ...
15
votes
2answers
3k views

How can I detect a rectangular region of interest in a picture?

Here is a downsampled input image I converted to greyscale. To select the rectangular region of interest we first preform preprocessing: ...
2
votes
2answers
461 views

How can I draw temperature 3D plot?

I want to draw temperature 3D plot based on given data points {{x1,y1,z1},{x2,y2,z2},...}. Here z coordinate is temperature.Am going to Show the temperature z in corresponding {x,y} coordinate. In my ...
2
votes
1answer
239 views

Integrate[(1 + x/n)^n*Exp[-x], {x, 0, Infinity}]

I evaluated Integrate[(1 + x/n)^n*Exp[-x], {x, 0, Infinity}] . thinking the answer should be approximately $\sqrt{\pi n/2}$. Mathematica gave me ...
2
votes
0answers
164 views

Why is FindRoot initial value far from the specified one?

I am trying to numerically find the root of a function that looks a bit like: 1/x - (SchurDecomposition[A[x]][[2]])[[1]], where ...
4
votes
2answers
686 views

Check Google PageRank for a given URL

Does anyone know how to write a Mathematica function that returns the Google PageRank of a given URL? I found a tutorial for achieving this in a bash script here, but I have no idea how to port this ...
0
votes
3answers
182 views

How to construct pairs in a list?

I have an expression like this, input = x[1] x[2]^3 x[5]^2; Fist step, we can get a list from the input expression, ...
-1
votes
1answer
113 views

FindFit and Integration errors

First off, appologies for what may sound like a newbie question, as I am very new to using Mathematica. I am trying to find a way to get Mathematica to give me an expression that would describe the ...
7
votes
3answers
494 views

Efficient code for solve this equation

We have $a*b*c=-1$, $\frac{a^2}{c}+\frac{b}{c^2}=1$, $a^2 b+a c^2+b^2 c=t$ What's the value of $a^5 c+a b^5+b c^5$? I tried ...
-1
votes
1answer
160 views

An issue regarding Eigenvalues function [closed]

Can anybody please kindly explain to me why the members of the output vector produced by the following example are not equal to zero? ...
2
votes
1answer
303 views

How to reject or repulse some points in a 3D cloud of particles?

I'm having an issue with a 3D distribution of points. The distribution is really nicely looking in Mathematica, but it is used in an OpenGL astronomy program (Celestia) to generate a nebula, with ...
4
votes
1answer
142 views

Identical code, different answers?

I'm having some trouble with identical code giving different answers. On a fresh kernel (MM 9.0.0.0, Windows 64-bit), running the same code, copy-paste, gives two different answers: ...
1
vote
2answers
608 views
4
votes
1answer
284 views

Remove the white margins of a Graphics3D figure

If the option Boxed is set to be False in Graphics3D, additional white margins may appear as ...
0
votes
1answer
289 views

Why won't ContourPlot accept a variable argument? [duplicate]

I have a list of linear inequalities which describe a (polygonal) region. I can use RegionPlot to visualize this region; but I'd also like to overlay this plot with ...

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