0
votes
1answer
119 views

joining lists based on content

I have lists created by other processing steps, which are basically constituted by elements like this: ...
0
votes
0answers
97 views

How to highlight a string pattern? [duplicate]

This is an example in the help pages (Working with patterns: Highlight Patterns): ...
3
votes
1answer
300 views

rasterListContourPlot With PlotLegends in Mathematica 9

Jens Nöckel has write functions about (List) Contour Plots with rasterized shading in Mathematica: http://pages.uoregon.edu/noeckel/computernotes/Mathematica/rasterContourPlot.html It works well. ...
2
votes
1answer
127 views

Generating a list of specific intermediate numbers associated with continued fractions

First of all, I don't know how ContinuedFraction[] or Convergents[] are implemeneted, and I think it is immaterial to my ...
0
votes
3answers
1k views

Fit line similar to power of trendline in Excel

Is there a way to fit a line similar to power trendline in Excel? Something in this fashion: Fit[data, {1, x, x^(-n)}, x] ...
3
votes
3answers
161 views

Picking certain pairs according to a condition [duplicate]

I'm a Mathematica beginner and can't find out a solution to my problem. I have a list of pairs of numbers, for example something like this, but much longer: list={{2., 3.}, {3., 2.}, {5., 4.}, {4., ...
1
vote
1answer
148 views

How can I nicely overlay fits for multiple arrays with ListPlot or ListLogPlot?

I'm plotting multiple lists with ListPlot[] or ListLogPlot[]: ListLogPlot[{ListA, ListB, ListC, ListD, ListE}, PlotRange -> {{0, 100}, Automatic}] I also have ...
1
vote
2answers
101 views

Automatically evaluating related cells

I have the cells: In[1]:= l = 2 + 2; In[2]:= l >= 5 After evaluating them: Out[2]:= False Is there a way to evaluate ...
2
votes
1answer
178 views

How can I change the MPS format in Linear Programming samples of Mathematica?

I am trying to play with some linear programming examples of Mathematica as ExampleData[{"LinearProgramming", "blend"}, "Equations"]. It gives me the MPS format of ...
0
votes
1answer
126 views

Reversing axes to get Poiseuille profile [duplicate]

I am trying to plot my velocity profile, similar to this plot (not the arrows, just the shape) Here is my function ...
1
vote
1answer
154 views

A weird thing about ListPlot3D [duplicate]

I plot the function f(x,y). x goes from 0 to 25 and y goes from 0 to 12. So, my plot should look elongated since the range of x is twice as long as the range of y. The problem is that, mathematica ...
2
votes
0answers
94 views

RSolve and incomplete gamma function

I am interested in how Mathematica uses the incomplete gamma function to solve difference equations. For example, if we have this inhomogeneous, 2nd order equation and use ...
11
votes
2answers
399 views

How can I make a cell that contains an image which can be shifted?

When you're looking at some help pages, they may have cells containing images which can be shifted within the cell by left-clicking and dragging the mouse. Here is a sample: ...
1
vote
1answer
167 views

Confused about Unevaluated

Why does Map[Unevaluated, Table[PauliMatrix[i], {i, 1, 3}] give {Unevaluated[{{0, 1}, {1, 0}}], Unevaluated[{{0, -I}, {I, 0}}], Unevaluated[{{1, 0}, {0, ...
3
votes
2answers
855 views

ODE and BVP: NDSolve errors

The mathematical problem is shown here. I tried to solve writing the ...
5
votes
6answers
687 views

A matrix-vector cross product

I want to do a cross product involving a vector of Pauli matrices $\vec \sigma = \left( {{\sigma _1},{\sigma _2},{\sigma _3}} \right)$; for example, $\vec \sigma \times \left( {1,2,3} \right)$. ...
4
votes
2answers
133 views

Strange behavior of Integrate

I'm trying to calculate the following integral using Mathematica 9.0.1.0 a11=Integrate[Abs[Sin[b+x]],{x,0,2*\[Pi]}] This should be a simple problem; however, it ...
1
vote
1answer
197 views

Notebook UI: Autocompletion - Display function arguments when typing?

Is there a setting to display the required arguments of a function when typing as Visual Studio, Matlab, etc. does?
9
votes
2answers
296 views

In what situation is the use of Directive required?

Sometimes I see code samples in the document or in this site using Directive, but I haven't yet find a case that Directive is ...
2
votes
1answer
110 views

Expand List Operation

On applying a multiplication and subtraction on a list, like so: x = 2y - 4; Where y is a list containing fractions of complex numbers generated from dynamic ...
3
votes
1answer
780 views

How to plot and solve the numerical solution of a integro-differential equation

I have a integro-differential equation of the form $y'(t) = - \int_0^t {y(t_1 )} e^{t_1 - t} dt_1, {\rm{ t}} \in {\rm{[0,10], y(0) = 1}}$ My code is: ...
5
votes
1answer
149 views

question about Inner [duplicate]

question1: (code 1 something wrong, Why? and how to overcome this to achieve the next code's effect) ...
0
votes
2answers
75 views

Replace expression using a tuple

Given an expression in x, y, z (for example), and a list with three elements, like ...
9
votes
1answer
405 views

FourierSeries for rational function looks wrong

I have the following code: ser[x_] = FourierSeries[(\[Pi]^2 + a)/(3 x^2 + a), x, 10] // N // Chop It gives me some series, which I then try to plot. And ...
4
votes
1answer
363 views

Checking if an expression is equal to zero

I have 6 points in $\mathbb R^3$ as follows: ...
3
votes
4answers
146 views

Rearranging a set of numbers

I have this set of numbers, that is a range of prices (ie 6-10) and a quantity of products (5) ...
2
votes
0answers
535 views

Calculate variance of random walk?

How can I symbolically calculate the variance of the following random walk in Mathematica? Given several discrete random variables such that $p(Z_i=1-2k)=p$, where $k$ is a small real number, and ...
2
votes
1answer
132 views

Cannot run Mathematica C-interfacing examples 'factor'

I am trying to run a Mathematica example concerning Mathematica interfacing issues with C programs. In particular I am trying to call a Mathematica function from C. Example ...
4
votes
3answers
169 views

How can I combine two Pick expressions into one?

I want to speed up my code, i.e., replace Select by Pick. I think using two Pick ...
27
votes
4answers
1k views

Compiling more functions that don't call MainEvaluate

I would like to use Compile with functions defined outside Compile. For example if I have the two basic functions F and G F[x_] := x + 2 G[x_] := x And I want ...
1
vote
1answer
389 views

What does the Error Message in DSolve really mean?

Having this ordinary non linear differential equation $$y'-x^2 (y+1)\cdot (y+2)^2= 0$$ with the boundary condition $y(4)=2$. When trying to solve this one with Mathematica by using ...
1
vote
1answer
241 views

how to reduce the time to calculate triple integral

i want to evaluate the following integral, but it takes 15 min to do it. i must reduce the time to calculate it, i have to do a table and create a graph, but takes too long. anyone have an idea ? ...
3
votes
3answers
676 views

Plotting heat equation in a Manipulate expression

I have a 2D heat equation $u_t = \alpha (u_{xx} + u_{yy})$ with conditions: $u(x, y, 0) = 300$, $u_y(x, 0, t) = \mu_1(x)$, $u_y(x, 1, t) = \mu_2(x)$, $u(0, y, t) = \mu_3(y)$, $u(1, y, t) = ...
4
votes
3answers
152 views

How to dynamically change the Appearance of a control in Manipulate?

How can I dynamically change the appearance of b? Strangely it works for the Enabled state but not for the Appearance. Thanks. ...
3
votes
1answer
263 views

Create a table with inline conditions

I am trying to create a table with conditionals inline. For example, I'd like to create a 2 dimensional table like this: ...
2
votes
2answers
212 views

FindFit: Fit that is always lower - Change of Norm?

I am trying to find a fitting function for a multidimensional set of data. I will have to find a fitting function that is always lower (conservative) than the data fitted. The easiest way is to look ...
0
votes
1answer
60 views

Don't pollute outside context when solving equation from the outside

This code works fine only if a is not defined in the outside context: ...
1
vote
0answers
253 views

webMathematica interface for Mobile apps

I was reading about webmathematica but it has mentioned that it is for websites and mobile apps depend on wolfram alpha to get its work done. But since exact mathematica code doesn't work in alpha, it ...
2
votes
2answers
288 views

How to populate a table using a rule replacement

I am trying to populate the rows and columns of a table by using a rule replacment. To generate a table that looks like this For example Sc would be row 1, column 1. An example of a record looks ...
1
vote
1answer
131 views

How to track dynamically generated manipulators?

In the code below the manipulators that are generated from the stakes buttons are not tracked by the Manipulate expression that contains them. How can I make the ...
4
votes
1answer
129 views

Minimize failing on a polynomial

Calling: Minimize[{-0.4877 - 0.1190 r^2 - 0.1885 r^4 + 2.9703 z - 0.5531 z^2, 0 <= z <= 3.5 ∧ 0 <= r <= 1.75}, {r, z}] returns ...
1
vote
1answer
136 views

direct assignment to the element in a Table

I have already asked a related question here why set values in this way doesn't work? But I think I have to write the question which I encountered explicitly? ...
54
votes
1answer
2k views

Open-source IntelliJIDEA plugin to support Mathematica development

Although we already had a question asking for development alternatives to Wolfram Workbench, I want to ask a more specific question: One of the most advanced IDE's especially for Java programming ...
13
votes
1answer
649 views

How can I conveniently call igraph through RLink?

Mathematica has lots of functions for working with graphs, but this functionality is not yet as mature as the igraph library. It is useful to have access to igraph from Mathematica, both for ...
10
votes
1answer
526 views

Mathematica equivalent of regex '\w{2,3}'

It beats me to write the Mathematica pattern equivalent to the regex: \w{2,3} Any ideas?
1
vote
1answer
250 views

How to normalize parts of matrix elements?

To normalize the last 2 or more columns of a matrix, ...
5
votes
2answers
288 views

DownValue “associative array” to list? [duplicate]

I have a "sparse array" like this arr[1.5]=0.4, arr[3.5]=0.7, arr[7]=0.3 which is not really a sparse array since the keys are not all integers. This is like a ...
2
votes
1answer
97 views

Help generating dynamic manipulators?

I would like to generate dynamic Manipulators for each of the selected buttons in a ToggleBar. How can I keep the state of each Manipulator in a variable? I would like to later access the values of ...
11
votes
1answer
393 views

Manipulate slider unresponsive after suspend in Linux

I've tested Linux Mathematica versions 7-9 on various Linux distributions, with identical problem: after suspend/resume cycle my Manipulate controls (i.e. sliders&buttons) appear unresponsive, ...
2
votes
2answers
398 views

CoordinateTransform from Cartesian to Spherical

I have a set of coordinates on the sphere in terms of cartesian coordinates. I would like to convert them to spherical data points. However, when I try to convert the point {0, 0, 1} it tells me that ...

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