0
votes
2answers
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 ...
0
votes
0answers
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 ...
2
votes
1answer
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 ...
4
votes
3answers
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 ...
0
votes
1answer
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 ...
0
votes
0answers
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 ...
2
votes
1answer
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 ...
14
votes
1answer
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: ...
1
vote
1answer
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 ...
19
votes
1answer
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: ...
1
vote
1answer
6 views
0
votes
1answer
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 ...
5
votes
3answers
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 ...
6
votes
3answers
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 ...
0
votes
0answers
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. ...
0
votes
2answers
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 ...
3
votes
1answer
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 ...
-3
votes
0answers
36 views

Function Expectation

I want to have a function result from this expectation is it possible? ...
1
vote
1answer
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] ]
-1
votes
2answers
51 views

Module function corrupts string? [on hold]

I have the module who should replace some elements of a matrix with checkboxes ...
3
votes
3answers
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 ...
5
votes
0answers
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 ...
1
vote
1answer
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 ...
8
votes
1answer
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: ...
19
votes
1answer
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 ...
23
votes
1answer
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, ...
-1
votes
2answers
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.
2
votes
1answer
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 ...
-1
votes
0answers
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 ...
5
votes
5answers
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 ...
8
votes
2answers
110 views

Unexpected result from StringReplace

The following works as expected. StringReplace["xxxyxz", "x" ~~ _ -> "ww"] "wwwwww" And so does this. ...
0
votes
0answers
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 ...
1
vote
0answers
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 ...
11
votes
2answers
153 views

Difference between Association and Dispatch

In the example below, Association has a different behavior from Dispatch: ...
0
votes
0answers
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 ...
3
votes
1answer
41 views

Is it possible to change the MinPrecision in command “Compile”?

I'm using "Compile" to do some numerical calculation and I need high Precision. I was wondering if it is possible to change the Precision in command "Compile" to some $MinPrecision?
3
votes
2answers
200 views

Speed up calculation

First of all thanks to: rm -rf, Mr.Wizard, Simon Woods, Pickett, Piotr Wendykier, Mac, Yves Klett, belisarius, halirutan, bill s, nikie, wxffles, ... Everybody of you helped me (a mathematica ...
1
vote
1answer
60 views

Derivative of a plot

I plotted a graph numerically, so there is no information of a function of the graph. Now i want to plot the derivative of this graph. Is there any way to do it in mathematica? I have the following ...
0
votes
1answer
56 views

My matematica notebook dosen't work,its bring syntax error ,why?

i have many matematica notebooks and all of them are working clearly besides one which is the most important for me.There is my whole project.Please someone help me.What should i do???
9
votes
1answer
126 views

Operator syntax for Merge-like Query

Bug introduced in 10.0.0 and fixed in 10.0.2 Is it possible to take advantage of Dataset's Query operator syntax to Merge parallel queries thereby avoiding Function's that are otherwise required? ...
-1
votes
1answer
51 views

How to integrate a generic integral? [on hold]

I'm trying to integrate this between $0$ and $T/4$: $$\frac{2}{T}V\int{Cos(wt)dt}$$ I use this in Mathematica: $$\frac{2}{T}(\text{Integrate}[V\int \text{Cos}[\text{wt}] \, dt,\{t,0,T/4\}])$$ But ...
2
votes
0answers
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 ...
1
vote
2answers
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. ...
0
votes
1answer
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 ...
1
vote
1answer
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 ...
0
votes
1answer
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 ...
0
votes
0answers
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, ...
0
votes
1answer
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 ...
1
vote
1answer
42 views

Ratio of variables AxesLabel is messed up when plot exported to pdf

On the vertical axis of a Plot whenever I have a ratio of variables in a string as axes label, the exporting of the plot to PDF format messes this ratio up. Minimal working example: ...
10
votes
2answers
186 views

Evaluate selection in new window or new notebook?

Sometimes when you have long code you need to check some part of this code. the way I am using currently is to selected the part that I want and then copy it to new notebook and then evaluate it ...

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