# All Questions

219 views

### Mark Minimum Value in DensityPlot

Let's take this example: DensityPlot[Sin[x] Sin[y], {x, -4, 4}, {y, -3, 3}] How do I retrieve the minimum value and position of the minimum of a plot from the ...
128 views

### How can I save a Manipulate's control settings to a dataset?

This is probably an extremely simple question. I have a manipulate that sets variables used to define an offset, amplitude, frequency and phase of a trigonometric function. ...
227 views

576 views

### Why don't some functions work in trial versions of Mathematica?

I currently use the trial version before I decide to upgrade. However, a number of expressions don't work, i.e. it results in some errors that I don't know how to interpret. For example, if I use the ...
122 views

### Systematic increase in runtime [duplicate]

When I run this simple code, which repeats many times the exact same operation (a differential equation), the runtime (given by Timing) increases systematically, ...
201 views

### Looking for ideas for handling a complicated fitting problem

I have the following data: ...
119 views

### What is the syntax to conditionally suppress plotting in version 9?

In Mathematica 7 it is very easy to conditionally suppress plotting of individual lines using If: ...
510 views

### How can we create a histogram distribution from binning data?

HistogramDistribution takes a list of data points, creates a histogram from them, and returns this histogram in a form that can be used as a distribution. I ...
378 views

### Labeling a grid

I have m = {{0, -1, -2, -3, -4}, {1, 0, -1, -2, -3}, {2, 1, 0, -1, -2}, {3, 2, 1, 0, -1}, {4, 3, 2, 1, 0}}; And a grid ...
187 views

### Why does Arrow not work well with Scaled coordinates in 3D?

I am a little puzzled by the fact that if I try to use Arrow with Scaled coordinates in 3 dimensions the arrowheads are all over ...
566 views

### Distance between two line segments in 3-space

I need to compute the distance between two line segments in a project. After googling, I found this algorithm and used it to implement a Mathematica version: ...
104 views

### SparseArray internal structure [duplicate]

According to the documentation: SparseArray is treated as a raw object by functions like AtomQ and for purposes of pattern ...
104 views

### FlipView can't handle CurrentValue[“MouseOver”]. Kernel crash

Is this code crashing your Mathematica session? (it can so look out :P) ...
106 views

### Why does a heavy background slow LocatorPane from updating, even if only the locators are Dynamic?

I'm having some trouble getting a dynamic plot to operate efficiently, and I think I've tracked down at least part of the problem to some pretty weird behaviour on the part of ...
163 views

### Parallel evaluation of Image and Rasterize problem

The following command: ParallelTable[Image[Graphics[{{Red, Disk[{5, 5}, 4]}}]], {i, 10}] shows a very strange behaviour. It starts a new Mathematica process on ...
200 views

### Simplification of integrals depending on a parameter [duplicate]

Assuming[Element[n, Integers], Integrate[Sin[x]*Sin[n*x],{x,0,Pi}]] returns 0, which is obviously wrong for n=1. ...
154 views

### How to impose control over vertex-to-vertex Graph edges?

I’m working on a Markov Chain and hope there is a way to impose control over how Mathematica places edges to connect vertices in a Graph. My Markov Chain currently consists of 4 vertices with 2 of the ...
232 views

### How to make a table of $\sum_{i=1}^n$?

I want to create a table of $\displaystyle \sum_{i=1}^n i^k$ for $1\le k\le 5$. The output I want to obtain is a TeXForm output as follows. \begin{align} ...
418 views

### Counting 'False' values at the ends of a list

I have table like this: t = {False, False, False, 4.5, 6.789, 1.23, 0.98, False, False} and I want to know how many False values I have at the beginning and at ...
357 views

### What is missing in this Mathematica Journal Article?

So I had been looking to solve a little tiling problem and Google turned up this Mathematica Journal Article and I noticed the code was both incomplete and incorrect, so... My Question is, What is ...
235 views

### Extracting data values from a plot

I found that the fact is very useful that a plot sometimes contains all the original data needed to reconstruct that plot. This is very helpful for me because sometimes I need to retrieve and analysis ...
304 views

### Convert array from {{…}} to “[[…]]”

I have made this function: conv01 = Map["["<>StringJoin@@Riffle[#,","]<>"]"&,Map[ToString,#,{2}],{0,1}]& to convert: ...
193 views

### How to delete mirror symmetric point pair efficiently

Look at following pic There are five points, I can generate the following point pairs ...
182 views

### Finding the maximal t at which u[x,t] == 1?

Given the smooth function u[x,t] on a domain, how do I find the maximal t at which ...
115 views

### Apparently contradictory output from Series and D

I defined a function as: g[b_] := Integrate[f[n]Exp[-b DA (n.u)^2], n] Obviously D[g[b], b] /. b -> 0 gives ...
316 views

### Why is Plot3D giving me a surface with gaps?

I am trying to get plot for the band structure for graphene. ...
566 views

### Perfect numbers

The question given to me: a. Find the perfect numbers between $1$ and $10^6$ b: Find the abundant numbers between $1$ and $1000$ For a, I wrote ...
73 views

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131 views

### The same analytical expression gets inconsistent FourierTransform results

I have an expression which is just a linear combination of plane waves, and I'd like to calculate FT of it. I know what I will get should be a bunch of delta functions, but it turns out Mathematica ...
732 views

### Better code to find Narcissistic number

My code finding Narcissistic numbers is not that slow, but it's not in functional style and lacks flexibility: if $n \neq 7$, I have to rewrite my code. Could you give some good advice? ...
236 views

### Ranking a vector containing ties

How can I rank a vector such that the ties are replaced by their middle ranks. For example, {1, 2, 2, 3}. I want to rank this vector but the ties must be replaced ...
398 views

### How to make a filled Ellipsoid?

I want to make a filled Ellipsoid, but it seems Filling options doesn't work in Graphics ...
192 views

### How can I use Dynamic to run a script when a new file is added to a directory?

I have an external program saving files to some directory on my hard disc. I'd like to run a script that imports and runs a script on each file as it is added to the directory. Is there a simple way ...
233 views

### Selecting a list from a list of lists

In working through Programming Paradigms Via Mathematica (A First Course) I have come across this two part question: A permutation of length "n" is a list of the first n positive integers in ...
182 views

### Keeping vertexcoordinates after adding a new vertex

I want to add a new vertex to a graph, with fixed VertexCoordinates but when I use VertexAdd, the new graph does not have the VertexCoordinates of the previous one. ...
323 views

### Changing a wave simulation

I want to adjust some code that I found on this Wolfram Demonstration: http://demonstrations.wolfram.com/WaterRipplesPassingThroughASlit/ Basically it shows a wave passing through a single slit. I ...
186 views

### Are there functions or packages in Mathematica to sort subsets in lex order, colex, revlex, etc.?

I am looking for non-canonical sorts of lists. A function that would give: Sort[X, "order type"] With "order type" being colex, revlex, etc.
362 views

### Mathematica inserts extra \left and \right for absolute values in LaTeX output

Type the following in a Mathematica DisplayFormula cell(other styles may also encounter this problem): Esc+l+|+Esc and Esc+r+|+Esc, and save as LaTeX. Note: See the difference of the character ...
458 views

### Plot the boundaries of each piece of a piecewise function

I'm wondering how to plot the boundaries of each piece of a bivariate piecewise function. Lets take for instance the following piecewise linear function $B_{111}(x,y)$: ...
259 views

### How to fix Ticks in Gauges?

Ticks is an option for Gauges. I fail, however, to apply custom Ticks to Gauges. For instance, compare these two: ...
609 views

### Numerical Integration as Model for Nonlinear Fit

I'm trying to do a fit for parameters of a function within an integral but I'm getting errors when I try and run it. Essentially I want the following fit to work out: ...
196 views

### Error messages from compiling the Piecewise function

The following works Compile[{{x, _Real}}, Piecewise[{{{0., 0.}, x > 5.}}, {1., 1.}]] but if I enter the Piecewise[...] in ...
584 views

### How to graph a series of coupled oscillators and watch the wave move along them

Here are the differential equations that set's up the 11 coupled oscillators. ...
1k views

### How to label axes in 3D plot adequately?

The following code produces plot with axes labels, which are jumping constantly. ...
547 views

### Transcendental equation with ContourPlot3D

I am still a newbie to Mathematica, so I am still getting used to the syntax and logic of the program - but I've been trying to do the following 3D plot: ...
611 views

### Wallis Formula and Pippenger Product---How do we get symbolic output?

The Wallis Formula computes $\frac{\pi}{2}$ OEIS and the Pippenger Product computes $\frac{e}{2}$ OEIS. Here is a combined formula: ...
176 views

### What is the fastest way to maintain a large set of expressions?

In my algorithm I need to maintain a set (an unordered list of distinct elements) of expressions supporting two operations: Test an expression for membership in the set Adding a new expression to ...
229 views

### How can I preserve the properties of edges of the original graph $g$ in a subgraph that doesn't include every edge of $g$?

The closest question to the following I could find was Preserving labels when using graph functions, but it doesn't seem to cover this. Consider a graph g where ...