4
votes
2answers
86 views

Replace Missing[Unmatched] with zero

After a left JoinAcross, I have a number of Missing["Unmatched"] values in my list of associations. I'd like to set them all ...
-8
votes
0answers
111 views

Visualizing The Crack of The RSA Cryptosystem [closed]

Q: how would you illustrate the RSA Cryptosystem with the new fast factorization technique? Side Note: This question is about Mathematica but it is not a home work. So, feel free do not publish your ...
5
votes
1answer
83 views

Grid rows height & SpanFromAbove issue

I would like to understand why the following code produces such a different result (Mathematica 9, Win7). Is this a bug? Is there a way to avoid this line height problem? ...
2
votes
0answers
70 views

How to code a simple audio equalizer? [closed]

I would like to code a simple Manipulate-based equalizer to make bass and treble adjustments in wav-file, but I haven't found any clues in documentation. Wiki says that I have to deal with linear ...
7
votes
5answers
299 views

What is my problem with MeshFunction?

I want plot the max value in a sine plot. We can use the following code ...
3
votes
0answers
74 views

Citation of the algorithms used in FindGraphCommunities

For my research work I need to put a comparison of different community detection algorithms. Instead of implementing all those algorithms once again, I would like to use the methods already provided ...
0
votes
0answers
54 views

Discontinuous Forcing for a Cancer Model — Issues with v9 NDSolve

I'm new here, so please be gentle with me and hopefully the post is appropriate and not too basic. I am a math teacher and use modeling in my courses. I had working code (in v8 of Mathematica) for a ...
0
votes
1answer
24 views

Why do I get the error: “The specified setting for the option FEFloatIterator cannot be used.”?

"The specified setting for the option FEFloatIterator cannot be used." This an error I am getting in a sizeable interface, containing 138 declarations in an outer ...
2
votes
0answers
69 views

An efficient way to merge a pair of 4d arrays of non regular length lists

Question I have two 4 dimensional non regular length lists of complex values. I have working code however it seems quite slow and I am not sure how I could improve this. Mathematically I am trying ...
0
votes
0answers
12 views

References to papers/books that uses a kernel to smooth a discrete distribution [closed]

Since a kernel, such as Gaussian, is often used to smooth out the distribution of discrete points in 1D, 2D or 3D, I believe there must be some study materials or research work that have used this, ...
0
votes
0answers
50 views

How can I display the numbers on the ordinate axis as exponentiation?

I create a Plot and I need to insert the values on the ordinate axis as exponentiation. For example if I have a value equal to 20000, view as 20x10^3. Here the code: ...
0
votes
0answers
71 views

Using one complicated equation to reduce another

(Relative noob here so don't assume much!) I need to use a vector equation (with $N-1$ entries) in the general form $y_j(x_{i,j},x_{i,j+1},x_{i,j-1})=0, i=1...3, j=1...N-1; x_{i,0}=x_{i,N}=0$, ...
2
votes
0answers
57 views

Blurred frontend text in Mathematica 10, Windows, High-DPI Display

So I have recently upgraded to a Windows ultrabook with a high-res display. All my software seems to cope just fine with the high resolution, except for Mathematica 10. Mathematica seems to pretend ...
-1
votes
0answers
51 views

Optimization: run this process multiple times [closed]

I am trying to minimize the objective function over [x,y]: Exp[x]*(4*x^2+2*y^2+4*x*y+2*y+1)+b subject to constraint ...
3
votes
2answers
133 views

Selectively updating individual graphics in a dynamic, multiple-plot Show

Suppose Show contains multiple graphics objects that differ markedly in the amount of computation needed for their display. Hence, when dynamically updating only ...
0
votes
0answers
23 views

In lambda calculus, can the parameter of abstraction be a non-variable lambda expression? [migrated]

In short, my main confusion is between the two concept variable and lambda expression: I am reading this reference here: ...
1
vote
0answers
17 views

Is it possible to pass a “shared” integer in librarylink?

MTensor supports shared pass, where the argument can be modified in the library function and that modification can be seen in Mathematica side. Is it possible to do the same thing to a integer or ...
1
vote
1answer
79 views

Locators, lists of variable length, all in Manipulate

I'm trying to implement a complicated Manipulate[] interface. I'm not really interested in working code, but for those interested, I would like the program to allow you to drag around a variable ...
4
votes
0answers
44 views

Listable compiled functions used in NMinimize

This is an example from MMA: cListable = Compile[{x}, (x-1)^2, RuntimeAttributes -> {Listable}] In case of single entry: ...
6
votes
0answers
90 views

Exporting a compiled function for later use

I compiled a function then used it in NMinimize. The computation took 19 seconds. Then, I exported this compiled function and restarted MMA and imported this ...
0
votes
0answers
55 views

Making a list of terms ordered by product order

I have some expressions f,g,h that are elements of a symmetric tensor algebra. The expressions are generated by a basis ...
5
votes
3answers
205 views

difficulty abstracting the OptionValue pattern

I am building lots of functions that use Options and OptionValue and wanted to reduce the redundancy in the expressions that ...
0
votes
0answers
40 views

Simplifying Products In Mathematica [closed]

I have, amoungst many others, the function: Kbox[n_, r_] = ((n - r)*r)!/ Product[Product[(r - i + 1) + (n - r - j + 1) - 1, {i, 1, r}], {j, 1, n - r}] ...
6
votes
5answers
274 views

Find patterns in a list

again, I have a list like this: ...
3
votes
1answer
107 views

Bad numerical approximations

I'm trying to do some calculations here, but for some reason Mathematica starts using numerical approximations that are no good for my work. Specifically: ...
7
votes
0answers
33 views

Proper EdgeForm setting so boundary appears entirely within shape

I have two neighboring (complicated) polygons that I want to be displayed with thick boundaries, however the two shapes border one another, and as EdgeForm places the line centered upon the polygon's ...
2
votes
1answer
95 views

FindFit with parameters which are simultaneously in initial conditions

I have RLC circuit. I would like to find R and L by using FindFit, but L is in initial condition and I have problem with it. Could you help me ? ...
1
vote
1answer
45 views

How to factorise a variable out of an indefinite sum?

(I should start by saying I'm a total beginner with Mathematica, so if the answer needs code I'll need it spelled out quite clearly, the learning curve for this is proving steep!) Basically what I am ...
1
vote
1answer
24 views

Dealing with dynamic tables [closed]

Making dynamic vector variables is difficult in Mathematica. For example: X=Table[ToExpression["x" <> ToString@i], {i, 0,4}]; X[[2]] Yields x1. However, if ...
5
votes
3answers
116 views

Creating Correlation Table (and Working) With Missing Data

I am working with data that contains missing values (I have several variables (across the columns) and several observations (across the rows) in an excel spreadsheet). Example of the data structure: ...
2
votes
0answers
35 views

How to apply Gaussian kernel to smooth density of points on 2D (algorithmically) [migrated]

I have a set of points on a 2D surface and need to build a heatmap. However, I also need to smooth out the density/distribution by applying some sort of kernel (Gaussian kernel, for example). I Know ...
3
votes
0answers
45 views

Bandpassing EEG's using Mathematica's Bandpass Function

Let's say we have an EEG signal approximated using a fractional Brownian motion: ...
2
votes
2answers
96 views

Plot help with axes coordinates

Plot[{4 - 2 y, (5 + y)/3}, {y, 1, 10}] How do I make Mathematica tell me the coordinates for cuts with the y-axis, other than just looking at it?
2
votes
2answers
62 views

Table with dynamic iterator

I would like to make a Table whose iterator has a dynamically updated endpoint, i.e. Table[i,{i,1,Dynamic[n]}] Is this possible? Here is the context: ...
10
votes
3answers
88 views

How to limit number of user-defined messages issued per evaluation

I have written code such that if it runs into a particular function, a warning message is issued. However, it is common for the program to call this function several times in a single evaluation, but ...
3
votes
1answer
74 views

Use Style on list elements

I have a list like this: list = {0, 0, 0, 1, 1, 1} I want to color all the 0's in red, but I dont want to count through all the elements, like in my solutions, ...
4
votes
4answers
215 views

implement the ZOH in mathematica [closed]

well I'm trying to implement the ZOH in Mathematica, but I can't. Take a look, this is my script: ...
-1
votes
0answers
59 views

Trying to solve a trig identity [migrated]

Given $\sin 2x+\sin x=1$, find the value of $\cos 2x+\cos 4x$. I know $\cos 2x+\cos 4x \implies 1-2\sin^2x+1-2\sin^22x$, but didn't get the answer.
2
votes
1answer
42 views

How to pick out terms in a linear equation with a positive coefficient?

Basically I have a really large output which looks like a long linear equation $AAA-BAA-CAA+DAA+...-ZZZ$ And I only am concerned about those terms that have a positive coefficient (i.e. a plus in ...
7
votes
2answers
258 views

When must I use the Return function?

In a comment to my answer to this question, QuantumDot asks, "Where can I find more information on when I must use the 'Return' function?". I found this too deep a question to be answered by leaving a ...
3
votes
1answer
67 views

What is the order of execution of Animate?

I used to think the execution order of Animate is the same as For until I find: ...
3
votes
2answers
88 views

Trying to solve simultaneous equations based on format found on official website [closed]

$\def\1{x_1}\def\2{x_2}\def\3{x_3}\def\f{f(\1,\2,\3)}\def\bs{\bigskip}\def\b{\begin{pmatrix}}\def\e{ ...
3
votes
1answer
80 views

How to combine Plot and GeoGraphics?

I want to combine this map as "background" of this combined plot. How can I do it? The documentation doesn't show any similar demonstration. ...
7
votes
3answers
156 views

Change appearance of ConvexHullMesh

I'm struggling to understand the behaviour of ConvexHullMesh (or rather the non-behaviour). I have a polynom p ...
4
votes
2answers
106 views

Adding a thick curve to a regionplot

Suppose we have the following simple RegionPlot: ...
0
votes
0answers
89 views

How do I set up conditions at infinity?

I having trouble with this equation: $$ -\frac{(2 m \text{U0}) \Psi (\rho ,z) \left(1-e^{-\text{} \left(\frac{z}{d}\right)^2-\left(\frac{2 \rho -(r+R)}{R-r}\right)^2}\right)}{h^2}+\frac{\partial ...
6
votes
2answers
188 views

How to get rid of the blank areas around alphabetical images?

I attempt to test the mean graylevels of the alphabets "W" and "Z". I used the following code to create the images of them. ...
4
votes
0answers
90 views

Is there a relatively quick way to solve my integer-valued equation?

This is a very simple problem. It can be solved by nested Forloops that exhaustively test every possible case, throwing out all non-solutions. Find all the ...
4
votes
1answer
147 views

How to find the integer solution number of a linear system with inequalities?

I have the following system with mixed equality and inequalities defined as: ...
6
votes
3answers
806 views

How to get the mean color of an artwork?

I got a piece of artwork in dimension of 20x20 pixels. I attempted to divide it into a 5x5 array of elements each of a smaller size of 4x4 pixels, and would like to find the mean color of the ...

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