# All Questions

401 views

### Multiple simultaneous events in EventLocator method for NDSolve

I'm using NDSolve to integrate a system of ODEs, and EventLocator to stop the integration when it leaves a certain region in phase space. This works perfectly as it should. However, I've also added ...
2k views

### Remove image background of headshot in Mathematica?

For example, using ExampleData[{"TestImage", "Girl2"}]: what's a general way to make the background transparent? I've tried various combinations of ...
315 views

### Dynamic lists as function arguments

Suppose I have a function that requires a list is as input. I.e. f[list_]:=DoSomethingWithList Now, if I pass a variable as Dynamic like this ...
153 views

### How to change type order in PearsonDistribution?

I need to estimate a Pearson distribution from a batch of tables tab: ...
969 views

### Controlling the 2D $x–y$ aspect ratio of a 3D plot

I have some data representing a nested list, each element being composed of 3 real numbers like ...
638 views

### Adapt ColorFunction in Array Plot

The problem I'm facing is how to adapt ColorFunction so that it ranges from green (low values) to red (high values): ...
743 views

### 3- dimensional plot of 2-dimensional systems of differential equations

Let's take this first example of a 2D output: ...
1k views

### AccuracyGoal, PrecisionGoal, WorkingPrecision and NDSolve

I'm trying to understand exactly what WorkingPrecision, AccuracyGoal and PrecisionGoal mean ...
503 views

### Can you call a C function that takes function pointers as arguments?

I want to use MathLink to call a function I wrote in C. However, similar to an integrator, it takes a function pointer as an argument and applies it on numbers depending on the other arguments. I ...
551 views

### Visualize cluster distances in DendrogramPlot

I want to perform a cluster analysis using the HierarchicalClustering package. Is there a way to display the inter-cluster distances in a dendrogram plot? An ...
174 views

### Why didn't Reduce give me the right result?

My code: Clear[r1, r2]; par[r1_, r2_] := r1 r2 / (r1 + r2); Reduce[{5 par[r2, 32000]/(r1 + par[r2, 32000]) == 1.8 && par[r1, r2] == 5000}, {r1, r2}] ...
193 views

### Can individual locators in LocatorPane be temporarily disabled?

This follows up on another question about the sensitivity of Locators in a a LocatorPane. I would like to be able to enable/disable individual locators in a LocatorPane. In the simplified version of ...
1k views

### Solve matrix equation A*X=X*B using LeastSquares

I want to solve matrix equation A*X=X*B using LeastSquares method, but it is suited for equation like A*X=B. All matrices are 3x3 ...
2k views

### Find the dimensions of a cylindrical can that will minimize the cost of the material

A cylindrical can is to be made to hold 1 L of oil. Find the dimensions that will minimize the cost of the metal to manufacture the can. This is a standard calculus problem. The volume of the ...
135 views

Recently I have been working on group theory and I have found checking for associativity for specific Cayley tables to be rather tedious so I wrote a program to do it for me. Most of the time I would ...
289 views

### Polynomial expectations of generic distributions

Summary Polynomial expectations depend only moments and cross moments of a multivariate distribution. I would like to use Expectation to compute polynomial ...
391 views

### Word Squares and Beyond

A word square is a set of words which, when placed in a grid, read the same horizontally and vertically. For example, the following is an English word square of order 5: ...
1k views

### Animation of Differential Equations from NDSolve with ParametricPlot3D and Evaluate

I have a system of differential equations (referred to as "s") and use NDSolve to obtain the solution. I substitute the interpolated functions for the original ...
207 views

### Efficiently importing XPM matrix data into Mathematica

The XPM file format is an image file format. Although it is primarily intended for icon pixmaps, it can also be used to store matrix data. For example, the GROMACS chemical simulation package uses ...
155 views

### How to get the boolean value of an inequality involving an InterpolatingFunction?

Here's the code: yan = FunctionInterpolation[x^2, {x, -1, 1}]; FullSimplify[yan[x] > -1, -1 < x < 1] Needless to say, what I expect to see in the output ...
2k views

### How to use filling in ContourPlot

I want to fill region between different contours, e.g. ContourPlot[{c1 = f1, c2 = f2}, ...] a la the filling options for Plot ...
184 views

### Trying to generate a function from InterpolatingFunction with FunctionInterpolation

Here is the code (I'm sorry to give you such a complex code sample but I failed to reproduce the error with a simpler InterpolatingFunction): ...
564 views

### What function can I use to evaluate $(x+y)^2$ to $x^2 + 2xy + y^2$?

What function can I use to evaluate $(x+y)^2$ to $x^2 + 2xy + y^2$? I want to evaluate It and I've tried to use the most obvious way: simply typing and evaluating $(x+y)^2$, But it gives me only ...
342 views

### Substituting Symbol font for Mathematica's custom font in exported plots and other graphics

Mathematica includes some custom fonts that allow you to use a wide range of mathematical symbols in output. For example, one can write: ...
387 views

### How do I transform a rasterized graphic's coordinates back to its original ListPlot data coordinates?

From this question I successfully made an elliptical fit for my data. However, when I try and collect the datapoints within the ellipse via this question the coordinates of my ellipse correspond to an ...
257 views

### Code to draw geometry doesn't run

I'm new to Mathematica and have no background whatsoever in programming, although I will teach myself soon. I was wondering if one of you programming pros could help me out. I received a code from ...
395 views

### simplifying equations [closed]

I have a question that seems easy but I can't solve it. I have an equation like: eqgama = -8.33208*10^56 g1 + 8.18264*10^56 g1^2 == -1.42093*10^56 I use the ...
621 views

### Adding Lines to Sparklines (plots w/o frames, axes, etc.)

I have been working with Sparklines, thanks to some code found here. Here is what I am using: ...
374 views

### Generating Linear Extensions of a Partial Order

Given a set $S$ and a partial order $\prec$ over $S$, I'm looking for a way to "efficiently" generate a list of linear extensions of $\prec$. Suppose the partial order is given by a ...
832 views

### How to use and input audio wav file into a Wolfram demonstration

I am trying to send a Wolfram demo, which contains a sound wav file. sound = Import["C:/myfile.wav", "Data"]; snd := sound[[1]]; or snd = sound[[1]]; Is it ...
879 views

### Chain rule while differentiating

I am trying to find the derivative of a function defined in polar coordinates with respect to $x$ and $y$. My function is defined as follows: \$ v_x(r, \theta ) = v_r \cos (\theta ) - v_{\theta }\sin ...
272 views

### Creating a list of PopupMenus that dynamically update an element in a list

So as the title says I am trying to make a list where each element is determined by a users choice of an element in a PopupMenu. My first attempt: ...
2k views

### Passing a matrix as a function argument

I am trying to do the following: ...
207 views

### How Can I Use Conditional with Rational Domain Restrictions [duplicate]

I am reasking this question in a new thread. My previous post How Can I Use Solve/Reduce Output? seemed to have led to a an interesting dissussion of how to (better) solve the problem that produced ...
198 views

### Delete contexts from a string representation of a symbol

I want to delete the string representing the context of a symbol. For info I need such a functionality in my ShowIt function defined here I'd like to know how I ...
652 views

### vectorial ODE in mathematica with matrix exponentials

I want to solve the following equation in mathematica : DSolve[{X'[t] == A.X[t], X[0] == ( {{0},{0}} )}, X[t], t] It is a system of 2 ODEs coupled by the matrix A, ...
235 views

### How do we turn off automatic smart quotes/special character substitution?

In Mathematica 8, whenever I enter "hello" into a cell of style "text", the quote marks are automatically converted to special characters: ...
567 views

### Can DSolve solve systems with unspecified function coefficients?

I am an economic research student with no previous experience with Mathematica, so please pardon me if my questions sounds really stupid. I am hoping to solve a system of nonlinear ODEs symbolically. ...
413 views

### Fastest way to sum pairwise potentials

I've been writing a function to sum a pairwise potential on two lists, i.e. two charged bodies, each containing N >> 1 and ...
588 views

### Reproducing Image Patterns with Mathematica

Surfing on the net I stared at this pattern. It´s a bamboo steam, and it´s awesome. I'm new to Mathematica so I'm a little lost, I'd like to try to reproduce this pattern, of course in a very ...
557 views

### Detecting and counting signals in list data: checking pulse rate

Hope this isn't too much of a basic question: I'm looking for some Mathematica functions, but I don't know which ones. Background I recently read about a simple technique for reading your body's ...
621 views

### Finding the roots of Hypergeometric1F1[]

I am trying to find the roots, λ, for this equation: Hypergeometric1F1[1/4 (2 -  λ /β), n + 1, β] for certain ...
756 views

Is it possible to avoid this unreadable situation with label crowding when using PieChart's RadialCallout and ...
663 views

### Mathematica - Dynamic - ListPlot - baseline

I am performing baseline fitting to a raw dataset on a two-state equilibrium process. The process involves fitting the sigmoidal curve to an upper and lower linear baseline, and subtracting so that ...
251 views

### How to print a message dialog window

I'm trying to figure out how to print a message dialog without printing the whole notebook. FrontEndExecute[FrontEndToken["PrintDialog"]] displays the print window ...
246 views

### How can I fix CDF Windowsize as constant

I want to make CDF WindowSize as constant so that the end user can not resize it either by dragging Window or by maximizing it. ...
1k views

### How Can I use Solve/Reduce Output

Suppose I want x and y to be rationals Solve[ x^2 + y^2 == 1, {x, y}, Rationals] I am ...
405 views

### PlotRange problems

I have a Delay Differential Equation of the form: ...