# All Questions

119 views

### joining lists based on content

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

### How to highlight a string pattern? [duplicate]

This is an example in the help pages (Working with patterns: Highlight Patterns): ...
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. ...
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 ...
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] ...
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., ...
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 ...
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 ...
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 ...
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 ...
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 ...
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 ...
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: ...
167 views

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, ...
855 views

### ODE and BVP: NDSolve errors

The mathematical problem is shown here. I tried to solve writing the ...
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, $\vec \sigma \times \left( {1,2,3} \right)$. ...
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 ...
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?
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 ...
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 ...
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: ...
149 views

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

### Replace expression using a tuple

Given an expression in x, y, z (for example), and a list with three elements, like ...
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 ...
363 views

### Checking if an expression is equal to zero

I have 6 points in $\mathbb R^3$ as follows: ...
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) ...
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 ...
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 ...
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 ...
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 ...
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 ...
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 ? ...
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) = ...
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. ...
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: ...
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 ...
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: ...
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 ...
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 ...
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 ...
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 ...
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? ...
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 ...
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 ...
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?
250 views

### How to normalize parts of matrix elements?

To normalize the last 2 or more columns of a matrix, ...
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 ...
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 ...