# All Questions

38 views

### Import Data using selection criteria

I imported a file (text and numbers) and made constructed this. e[[1,All,{1,2,3,4,6}]] Column 1 is the name of the state. How can I get a subset of this where, say Column 1 is not equal to "New ...
8 views

### Specifying and solving a PDE on an L-shaped domain

I wish to solve Laplace's equation with Dirchlet boundary conditions on an L-shaped domain as described here http://www.inf.ethz.ch/personal/tulink/FEM14/Ch1_ElmanSyvesterWathen_Ox05.pdf I know how ...
24 views

### 'eps' equivalent in Mathematica

In Matlab there is a function 'eps'. eps Spacing of floating point numbers. D = eps(X), is the positive distance from ABS(X) to the next larger in magnitude floating point number of ...
103 views

### How to close external app from Mathematica?

Is there any analogue to SystemOpen for closing applications from Mathematica? Documentation says: SystemOpen["file"] is essentially equivalent to double-clicking the file icon in your operating ...
55 views

### Differentiating two tables x and y?

I have two tables x and y with x={673,674,675,...} and y={0,1,2,...} and delta=dx/dy. I would like to know how delta can be calculated knowing that delta is the derivative of x divided by the ...
16 views

### ErrorListPlot with errors on both axes

I am trying to plot some data with errors on both variables: tihs is what I do ...
43 views

### Dynamic overlay of graphics and plot while maintaining uniform coordinates

I have a plot and a graphic that I want to overlay onto one another while retaining a uniform sense of coordinates throughout the whole thing. I have tried to do this two ways and both suffer from ...
197 views

### Why some built-in functions are slow

I just wonder why some built-in functions are slower compared to some other ways using more than one built-in functions for doing same job. consider this example: ...
31 views

### Joint Distribution with a Constant

I would like to simulate from a joint distribution multiplied by a constant. e.g. 3*NormalDistribution[0,1]*NormalDistribution[1,1] I tried using something like ProductDistribution but that doesn't ...
351 views

### Total much slower in version 10

Compilation nowadays may give very fast functions. Here is an example for finding the sum of a list of machine numbers, just as the built-in function Total: ...
6 views

### How to share ChartLegends among multiple BoxWhiskerCharts in GraphicsGrid?

First, create two BoxWhiskerChart: box1 and box2 ...
25 views

### Product Distribution with Copula

I am trying to create a joint probability function that is of the form: f(a,b,c)=f1(a).f2(b).f3(c).copula where ...
138 views

### Is it possible to find generating functions of infinite sequences with Mathematica?

I'm trying to find the generating function of a sequence as $(0,1,0,1,0,1,\dots)$ but reading Mathematica's help on FindGeneratingFunction[] seems to tell me that ...
52 views

### Minimizing a function with a constant $l > 0$

I'm VERY new to Mathematica and would like some help with minimizing a function. $$f(x) = \frac{1}{2} \sqrt{\frac{\left(l^4+x^4\right)^2}{l^4 x^2}}$$ I want to find which $x-value$ (probably ...
18 views

### Help needed for solving nonlinear ODEs

I want to solve fourth order nonlinear ODE with known boundary conditions using Predictor Corrector methods, or shooting methods in Mathematica but don't know how to solve them with these techniques. ...
40 views

### PEANO Integers using successor function

I'd like to define the integers and operations on it by using terms. Starting from zero->init[] and nth->succ[n-1th] where succ[] is the successor function. I ...
149 views

### ArrayPlot copied to PDF shows blurred mesh

Certain (but not all) images displayed in ArrayPlot, and then copied to PDF, show what appear to be fuzzy mesh lines in white areas. An example is shown below. I ...
36 views

### Function Expectation

I want to have a function result from this expectation is it possible? ...
64 views

### Strange interaction between Module and ListPlot

Why is the variable a ending up assigned to {1,2,3} after executing Module[{a}, a=Range[3]; ListPlot[a] ]
51 views

### Module function corrupts string? [on hold]

I have the module who should replace some elements of a matrix with checkboxes ...
93 views

### Colorize an image using two parameters

I have a matrix of data. I use Colorize[Image[Rescale[data]],ColorFunction->"Rainbow"] to create an image from the data where the value of each pixel is used ...
105 views

### Is there a package or canonical way for writing test harnesses in Mathematica?

I've written a complicated function foo.1 I'd now like to simplify this function's code, and later enhance it with more features. With each change, however, I'd ...
36 views

### Discrete Fourier Transform with x axis data?

Usually, Fourier Transform in mathematica is supplied by y data only, like the famous Sin[x] transform example. What if my data is a list of ...
507 views

### Problems with “Test Connectivity” and the Pacletserver

I know there has been a similar questions to this already but the solution did not work for me so here again: I have internet connection and I can execute such commands like: ...
1k views

### Web Browsing Automation with Mathematica

I want to build a bot to automate web browsing, this mean something like: filling forms press "submit" buttons find certain text inside pages and so on... How can I do this with Mathematica? The ...
263 views

### StringCases is Confused with Patterns in Version 10.0.1

I observed the following with StringCases when trying to use rules/patterns. Here is a screenshot of the behavior: Not only is the pattern highlighted in red, ...
98 views

### Palette for pasting matrix templates into a notebook

How I can build a palette of matrices?. So, I would like a palette with a 3x3 square matrix, a square matrix 4x4, 1x3 row matrix, 1x4 matrix row, column matrix 3x1 and 4x1 column matrix.
64 views

### EMF format imported in Word looks worse in version 10

In my work, I frequently use the "CopyAsMetafile" and "Paste" function in my Word document. Recently, I started working with Mathematica version 10 and negatively surprised that the display of ...
10 views

### Interpolation using 3 input function [on hold]

I'm trying to interpolate a function: I have 3 inputs: x1,f1 x2,f2 x3,f3 and I want to have at the output a function of f1, f2 and f3. xout=g(f1,f2,f3) I don't know how to do it on Matlab. the ...
171 views

### Select a particular rules out of a list

rule = {beta -> 4, alpha -> 2, x -> 4, z -> 2, w -> 0.8} Select[rule, beta] Select[rule, beta &] Select[rule, beta -> _ &] How would I ...
110 views

### Unexpected result from StringReplace

The following works as expected. StringReplace["xxxyxz", "x" ~~ _ -> "ww"] "wwwwww" And so does this. ...
28 views

### Can I use Interpolating function as an input in another NDSolve?

it´s my first time here, so let me know if I've not been clear. I'm trying to solve a numerical diferential equation, but my equation contains two numerical solutions from a previous problem. Of ...
33 views

### Astronomy: Transform coordinates from horizon to equatorial

I'm using Mathematica 10. Giving a longitude & latitude on Earth, giving a local time, how can I transform Horizon Coordinte (az , alt) to Equatorial Coordinate (RA , DEC). Use function so I can ...
153 views

### Difference between Association and Dispatch

In the example below, Association has a different behavior from Dispatch: ...
27 views

### coordinate system problem

I had an issue about the coordinate system of mathematica. I have a {800,600} image acquired with a camera. The projection matrix P of the camera is calculated using the calibration task. Now, when I ...
41 views

46 views

### Drop all powers from multinomial [on hold]

How to automatically replace an expression like x^3 y + x y z^2 by x y + xyz in Mathematica, i.e. replace all ...
98 views

### Josephus problem

See the Josephus Problem. My code takes in two numbers; one is the number of participants, and the other is supposed to be the number of players skipped between executions. ...
37 views

### Replace variables and redefine a function

I would like to redefine a function f(x)=1+2x^2 to a new function g(y)=1+2y by using the replacement ...
74 views

### Disable alert message with internet connectivity off

I work in an environment that has mathematica's internet connectivity turned off under Help > Internet Connectivity. Recently, after installing mathematica 10.0, every time mathematica is loaded it ...
27 views

### How to use rules in simplify this expression?

D[1/(1 + Exp[-x]), x] % /. {1/(1 + Exp[-x]) -> p} Suppose I know that the rule can be applied, but Mathematics just won't do it straight away as the expression ...
21 views

### Export to PDF file and use in latex, weird behaviour from using Acrobat

I have put all files here. All pictures are Exported from Mathematica 10.0.1 X64 (win7) using Export["filename.pdf",plotobject]. I first complied the latex file, ...
60 views

### Matrix form of complex numbers

Complex numbers have matrix form. But some 2x2 matrices while differ, represent the same complex number. To compare complex numbers one has to transform the matrices to the form \begin{pmatrix} a ...