1
vote
1answer
488 views

How to plot population growth model?

How would I draw the graph of a function dy/dt=((Ry^2)/T)-Ry in Mathematica? I have tried a few times but the constants are confusing me.
3
votes
2answers
313 views

Is there a way to “lock” some cells in a notebook?

Is there a way to "lock" some cells in a notebook so they can't be edited? It's usually input cell that's documenting some functionality. I'd like other readers of the notebook to be able to execute ...
1
vote
1answer
241 views

How to find 4 unknowns?

There are 4 unknowns constants: a,b,c,p. The variable is ...
3
votes
1answer
85 views

Is it possible to print more than last line with Get (<<) without using Print commands?

I want to run my Mathematica scripts from the terminal and I want it to print lines like MATLAB would. That is, suppress output by ending a line with ;, and ...
3
votes
4answers
229 views

How to create a composite function from a variable number of components?

Background of the problem: A patient takes a drug every $X$ hours with a half-life of $Y$ hours. How much of the drug will be (exactly) in his system after $h$ hours? For $X=24$, and $Y=24$ I made the ...
0
votes
1answer
578 views

using Mathematica's matrix multiplication in C++

Is there any way that I can utilize Mathematica's matrix multiplication in a C++ program? I'm making a 3D graphics engine (for class) in C++ and I would really like to use Mathematica for all of my ...
43
votes
2answers
2k views

Detecting grid lines in a raster image

Motivation: Last October 7 there was a presidential election in Venezuela. Although the opposition saw an unprecedented increase in its votes, the government votes increased even more resulting in the ...
11
votes
3answers
561 views

Labeling plots without evaluation

This is my first question here so please excuse my mistakes. Let us consider a rather contrived example: ...
9
votes
4answers
490 views

How to implement dual numbers in Mathematica?

I wonder how can I implement dual numbers in Mathematica, so that all functions work well with them (as with complex numbers). Particularly, for each function $f$, ...
7
votes
2answers
289 views

Select Cells to End of Notebook

I'd like to create a keyboard shortcut that will allow me to select all of the cells from the current cell until the end of the notebook, similar to how ShiftCtrlEnd functions when editing text in ...
9
votes
3answers
3k views

Given a Table of Plots with some parameter, how would I mark each of the plots with that parameter

I've got a two variable function that I'm plotting against one axis for a few different values of a parameter ...
0
votes
0answers
156 views

Reducing a statement with Mathematica, step by step [duplicate]

Possible Duplicate: Get a “step by step” evaluation in Mathematica I have a list of inequalities combined with quantifiers. And Mathematica is able to reduce to simple statement with the ...
5
votes
1answer
278 views

How can I compute the chromatic index and number of a graph?

I saw a recent question from M.R. and realized there is no function to compute the chromatic index and number of a graph, other than a really slow method in the now deprecated Combinatorica. So, how ...
12
votes
5answers
740 views

How to improve this code for solving the “Mr.S and Mr.P” puzzle?

Mr.S and Mr. P puzzle — "Formalization of two Puzzles Involving Knowledge", McCarthy, John (1987) We pick two numbers $a$ and $b$, such that $a\geq b$ and both numbers are within the range ...
8
votes
1answer
632 views

Prevent PopupWindow from opening multiple windows

PopupWindow objects can be clicked multiple times, opening multiple popup windows for the same object. How can I prevent this? A bit more detail: I have an ...
5
votes
2answers
210 views

How to protect pattern or subexpression when distributing / expanding expression?

I've got an expression like expr = (1-x)(a+b) that I would like to distribute / expand while keeping factors of (1-x) intact, ...
5
votes
1answer
411 views

Numbering element in descending order

How can I numbering the elements in descending order of second elements of sublists? For example, if I have the list which is ...
2
votes
3answers
245 views

Adding elements in the sublists

How can I add the elements in the sublists? For example, if I have the list which is m={{1,3},{2,3},{4,1}} then, the output that I want is ...
2
votes
0answers
941 views

Set Global Maximum Precision

I'm sure this has been asked before, but I've looked around and can't figure it out: How do I set a global maximum precision for a notebook (or in general, globally)? I have a large notebook in ...
4
votes
1answer
367 views

Plotting an inequality with “plot” axis

Whenever I try to plot an inequality with "RegionPlot", all my plots come out in boxed frames. Is there a way to plot inequalities where I get my standard x and y axes crossing each other? For ...
6
votes
2answers
739 views

Why does importing a URL fail the second time and produce a FetchURL::conopen error?

I have Mathematica code that uses Import[] to download URLs. I noticed that first time I use the Import[] command it works. ...
4
votes
1answer
260 views

Maximizing functions with Which statements

I'd like to be able to find the maximum value that my Capex function (see below) generates. This is a fairly simple function so I could just add it up but I have more complex functions of a similar ...
5
votes
1answer
187 views

Why are my images not printing at the expected size?

I understand how (in theory) to get images to be a specific size in inches, but when I follow the documentation, all of my output seems to be scaled down by a factor of a bit less than 70% (e.g., ...
2
votes
1answer
107 views

How can I get NotebookPrint to pass through the system print dialog?

As near as I can tell, NotebookPrint goes directly to the default printer, without employing the system standard process of opening a print dialog first. ...
6
votes
1answer
150 views

How can I restore context menu functionality to a Manipulate that contains Locators?

Before adding a Locator to a Manipulate, I can easily print or export the result using a context menu: But after adding a ...
3
votes
0answers
214 views

Mathematica Complains about Non Symmetric Covariance matrix, when it's not the case

I was doing some fitting with Mathematica7 using NonlinearModelFit. It's quite long the program to do the fit and that's why I am not displaying here ... It goes ok, and I can get the fit parameters ...
3
votes
2answers
282 views

Deleting a row or column of an adjacency matrix while maintaining the associated label

I am currently working with a weighted adjacency matrix for a directed graph, and it contains several 0 columns and rows. With the unaltered matrix, I am able to monitor the relations between vertices ...
4
votes
0answers
196 views

FinancialData property value at a given date

I was trying to get the volatility value of a specific equity on a given day. Based on the Mathematica Help, the syntax is ...
3
votes
3answers
227 views

SetAccuracy behavior

I'm puzzled by the output I get from SetAccuracy. According to the documentation, when SetAccuracy is used to increase the ...
3
votes
0answers
269 views

How to save (large) data generated from simulations

The following is a simple example of a much larger simulation that I want to run Define some processes ...
6
votes
2answers
182 views

Load Mathematica packages from the network

Is it possible to load packages (.m) directly from the network (http, https) without installing it locally?
6
votes
3answers
439 views

Plotting $\omega(k_x, k_z)$ in $(\omega, k)$ plane with assumption of $k^2 = k_x^2 + k_z^2$

I'm currently studying atmospheric-gravity waves and their dispersion relations. For analysis I need to plot the dispersion function: \begin{equation} \omega^4 - \omega^2\cdot C_s^2(k_x^2 + ...
2
votes
5answers
421 views

How to leave function unevaluated programmatically?

Is it possible to write a function in such manner, that it can be either evaluated or left unevaluated? This is a general question. Sample below is just a sample. No need to find solution for this ...
9
votes
1answer
249 views

The only usage for the option InterpolationOrder in NDSolve is to be set to All?

We know that changing the option InterpolationOrder in ListLinePlotListPlot3D、...
6
votes
2answers
402 views

Plotting All Possible Points Belonging to a Group Orbit

Given that $$X = \{(x,y,z) \in \mathbb{R}^3 |\, x^2 + y^2 + z^2 - 2(xy + xz + yz) = k\}\,,$$ where $k$ is a constant. Also given that a group $G$ is represented by $$\langle g_1,g_2,g_3|\, g_1^2 = ...
0
votes
1answer
82 views

What exactly happens when adding a Blank after a built-in function used in the rules of ReplaceAll?

Well, this question is just for curiosity, personally I never use ReplaceAll like this: ...
2
votes
1answer
132 views

Implementing a For (?) or series or loop (?) for individual results for every x to n

I'm working on improving a modeling formula and have spreadsheets worth of data to use, but my work so far has been quite tedious. I'm essentially pulling 20 rows of data from each separate sheet of a ...
7
votes
1answer
898 views

How to eliminate the backward play in Export of Manipulate?

I find that the Export of Manipuate contains backforward play, see a simplified example: ...
16
votes
2answers
900 views

How to compute the inverse CDF properly?

Note: this has been fixed in version 9. I want to compute the CDF and inverse CDF of the hyperbolic distribution: ...
6
votes
0answers
109 views

Doing computations in a modulo ring

I need to perform some computations in a modulo ring, like Mod[Subfactorial[n], m] Mod[Binomial[n, k], m] However, this is obviously much too slow for large ...
3
votes
1answer
357 views

using interpolation functions in ParallelMap

Edit I am editing the question to give a simple workable example. It is at the bottom under the heading Example. The original question is now headed withe Background. Background I am trying to ...
4
votes
1answer
1k views

Visualize eigenvectors at specified points?

I am very new to Mathematica and I got stuck about visualizing eigenvectors 2D and 3D. I want to visualize my largest eigenvector field of tensor data(15x15). I wrote this code for instance : ...
4
votes
1answer
113 views

Setting a binary operator Flat

I defined a binary operator in as the first statement in a new Mathematica notebook. {x1_, y1_} ⊕ {x2_, y2_} := Module[{}, Print["do anything"];] where the code ...
3
votes
1answer
365 views

How to implement Condition programmatically?

I am writing my own symbolic functions with custom symbolic properties. So often I wish to introduce some automatic simplifications or evaluations, which return the same head as it's argument. This ...
0
votes
1answer
177 views

how to get modify the following correlation matrix with a specific list of financial prices?

The following takes the last 5 members of the Dow Jones index and plots the correlation matrix of the last 5 years of daily prices: ...
5
votes
2answers
779 views

Can the CholeskyDecomposition function in Mathematica be made to work on non-symmetric matrices?

The CholeskyDecomposition[m] function in Mathematica requires a symmetric and positive definite matrix m. For instance, the ...
0
votes
0answers
69 views

How to create a dynamically self-updating table of content for a notebook? [duplicate]

Possible Duplicate: Generating a table of contents How to create a dynamically self-updating table of content for a notebook? The TOC should contain the titles for the section, subsection, ...
12
votes
1answer
2k views

3D plots with parallel projection

It is easy to make 3D Plots with Mathematica, e.g. use: Plot3D[Sin[x+y^2],{x,-3,3},{y,-2,2}] But I want to have nice plots in my thesis, so I decided to use ...
1
vote
1answer
812 views

Using singular value decomposition for graph clustering

I have a fairly large graph (50-60 vertices) with directed, weighted edges, and I am attempting to cluster the vertices. Prior to this, I have only worked with undirected graphs having symmetric ...
12
votes
0answers
593 views

Dual complex integral over implicit path using contour plot

Context I am interested in doing double contour integral over paths which are defined implicitely. For the sake of debugging, let's assume its $$\oint_{\cal C}\oint_{\cal C} \frac{1}{u\, x} d u d x$$ ...

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