# All Questions

139 views

### Rotating a a set of points in a square boxed region by $90$ degree increments [closed]

I have a set of two-dimensional points $P$ in a box with dimensions $(d_1,d_2)$. The coordinate for the lower-left-hand corner of the box is $(0,0)$ and the coordinate for the upper-right-hand corner ...
133 views

### Ways to access lists inside lists

I have gone through some reference material but I am not getting really good links that will help me grow understanding of ...
407 views

### ItoProcess function

While looking in the help manual of Mathematica concerning the ItoProcess function I found the following: ItoProcess[{a,b,c},x,t]: represents an Ito Process y(t)=c(t,x(t)), where ...
513 views

### Forecast Future Stock Prices - Brownian Motion - Again

excuse me, I think I have here a technical problem with Mathematica yesterday I posted the question with the title: Forecast Future Stock Prices - Brownian Motion I am still not very experienced but ...
60 views

### Abridging Lists of Equations within NDSolve, Manipulate [duplicate]

I have a pretty little NDSolve function that I've finally decked out with manipulatable (by sliders) coefficients, which changes the graph in real time. However, I ...
154 views

### Mismatch between Axes -> True and Frame ->True

Using Axes -> True of the following........ ...
126 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? ...
579 views

### Mathematica plots a discontinuity in piecewise function that does not exist [duplicate]

I have the following function defined: ...
98 views

### SetPrecision with indexed variables

I have an expression as below: ...
295 views

### How to define a vector with automatically added symbolic elements with subscripts

I want to define a vector lets say k containing elements Symbolize[Subscript[k, 1]], k2, k3 ... etc. When I define lets say k4 . I want the symbol automatically added to vector k. Something like ...
214 views

### Data structure for a list of actions

The idea: I need to generate a sequence of events then run a "propagator" over the list of events where the "propagator" will update the state of the following event. I can then write functions that ...
175 views

### Extracting information from list

I have a huge list that looks like this: ...
149 views

### Control maximum value of a slider with another control

Is it possible to make $y_{max}$ of Slider[y, {$y_{min}$,$y_{max}$}] depend on another control? For example, I have three variables (Time, Type1, Type2). I want a drop down box for the user to ...
435 views

### 3N-dimensional integral

I'm trying to compute a multidimensional integral with a variable number of dimensions. The integral is as follows: $$\int d^{3N}\!p~e^{-\frac{\beta}{2m}\vec p^2}.$$ I have tried this ...
434 views

### pointer like operations in mathematica and evaluation control

I would like to create a data structure of the type "header[pointer]" where pointer would point to a list. I will shown on an example how I'd like this to work, and where the problems are. ...
709 views

### Problem with transparency when I export an eps file

I have the following simple Mathematica code: ...
379 views

### NDSolve problems of convergence

I have a big function that I have to maximize, so I have to evaluate some equation with thousands of different values of the parameter. But the FindMaximum returns me many errors. I have traced the ...
414 views

### Controlling the speed of Manipulate animations exported to SWF

I would like to export in .swf a "Manipulation" output. I am using ...
1k views

### How do I plot x[t] vs. x'[t] (where x[t] and x'[t] are solutions to NDSolve)?

I have a differential equation which I solved using NDSolve. I can easily plot x[t] vs. t, x'[t] vs. t, but.... how do I plot x[t] vs. x'[t]? I tried using the Evaluate function to simplify things, ...
77 views

### Exporting CellFrameLabels to HTML

I have a notebook that has several cells with CellFrameLabels and I'd like to export the notebook to HTML. However, the CellFrameLabels are lost during export. Here's an example of what I'm working ...
215 views

### How to create a list of variable names to some function of that variable

For example, for a single variable I can write Print[Unevaluated[a], "=", f[a]] But if I try the next thing I'd think of doing, assuming I want a list, it ...
294 views

### How can I enhance ImageCompose to blend multiple layers?

Blend modes (or Mixing modes) in digital image editing are used to determine how two layers are blended into each other. Version 8 has functionality to perform binary and basic alpha blending but ...
3k views

### Creating a data1 versus data2 plot?

I have a table of data with multiple rows and columns, and I have to make a versus data table using two of these columns. Essentially, I have to set one column of data (column 3) as the y-axis and ...
62 views

### DynamicModule with Plot and EventHandler, take 2

I'm trying to build an animation in Mathematica that shows the evolution of a stochastic process, and when I click on the plot, the trajectory continues with different parameters. I have used ...
283 views

### Table - find index of the maximum element [duplicate]

Let's suppose that I have table t = {1.23, 3.4, 10, 34, 1.78, 0.98, 12.56}. To take the biggest element I can use Max[t] ...
146 views

### Better way to plot multiple discrete PDFs?

I often find myself trying to plot multiple PDFs for my courses. I find the default tools available to me are lacking and/or cumbersome. After readings some suggestions here, I have come up with the ...
47 views

### Why are fonts in my notebooks grainy after transferring to a new machine? [duplicate]

After transferring Mathematica (and successfully transferring my license) to a new machine (a Retina MacBook Pro) all the fonts in my documents look jagged: How do I get Mathematica to show smooth ...
68 views

### How to get the indices of values in a list which are NOT an specific integer?

I got a real array A, of which the Dimensions[A] is {5000,5000,5}; Some of the values in A are -1 , others are not. How can I Position[] the indices of those values which are NOT -1?
119 views

### Taking averages at certain intervals

I am trying to take averages of a large two dimensional array at certain intervals. For example, for the first row, I want to take K averages of 500 values. Here is what I am trying ...
174 views

### Avoid trigonometric simplifications?

When evaluating the expression Sinh[x]^2 + Cosh[x]^2 // FullSimplify I get Cosh[2 x] That is indeed a simplification, but ...
706 views

### discrete Fourier transform

As an answer to my code I will get a periodic discrete time dependent function called "data" which I want to get a Discrete Fourier transform of it using just one period of it,but I think some thing ...
103 views

Why does ...
541 views

### Optimization of a portfolio of stocks

I would like to use Mathematica to perform an optimization of a portfolio composed by 10 stocks. I did the first part to compute yields and expected yields, but I don't know how to finish the ...
181 views

### Gamma Incomplete Function representation in Mathematica and Matlab

I am confused about Gamma Incomplete function calculation in Mathematica and MatLab: For example, in Mathematica: Gamma[5,3] = 19.56 But in MatLab: ...
118 views

### Mathematica output in ASCII or larger text size for the output?

I am trying to read the output of this code that has crosses, circles and spaces. For some reason, the output is in very-very small alphabets so I would like to get it in ASCII and/or in larger ...
1k views

### Determine the 2D-Fourier transform of an Image

I am new to Mathematica and using Version 8.0. I want to calculate the 2D-Fourier Transform of a digital image and see its Magnitude and Phase Spectrum, and reconstruct it.
85 views

### Simplify looks ugly [closed]

I use Simplify mostly to make expressions look neat. However, Mathematica often does not produce expression in, what I consider, the optimal way. Look at this: ...
306 views

### Why does LogLinearPlot sample its argument outside the specified domain?

I experience a weird bug in the function LogLinearPlot. If the input is an interpolation function, such as the one created like this, ...
140 views

### Symbolic derivatives are being calculated numerically

Just found the following while debugging a problem. Mathematica is calculating the derivative of IntegerPart[x] in some odd way: ...
213 views

### Upon PDF export, edgeless rectangles do not tile perfectly, and corners may be cut. Is this a bug?

Exporting the following as a PDF file Graphics[{ {Red, Rectangle[{0, 0}, {1, 1}]}, {Green, Rectangle[{1, 0}, {2, 1}]} }] does not produce perfectly tiled ...
730 views

### Converting a large floating-point number to a single-line string

When I feed a large (or small) enough floating-point number to ToString, it produces a two-line string, with the first line containing only the exponent of 10: ...
121 views

### Possible to draw an Item in a Grid with only 3 sides of a Frame?

I'm trying to draw a Grid of characters where some of the characters have Frame lines on 3 sides. For example: ...
339 views

### Equivalent Nested Loop Structure

Consider the following examples: ...
742 views

### Evaluation of a triple sum does not finish in reasonable time

I'm trying to compute the following triple sum, but no result is produced within a reasonable amount of time. What to do? ...
169 views

### How to get an adaptive frame which fits auto-wrapped text? [duplicate]

When using the built-in Debugger, the breakpoints and the current step will be framed looks like this: My favorite part is, those frames are adaptive to the text when window width changing makes it ...
278 views

### Using uniform coloring in MatrixPlot

I have a rectangular matrix, which is m-by-10. Each element is either 0 or 1. I would like 0 to correspond to white elements, and 1 to red elements. This works ...
2k views

### How do I draw a DensityPlot in polar coordinates?

I am trying to plot $J_m(\chi_{mn} r) \cos(m\phi),$ where $J_m(\chi_{mn}) =0,$ as a DensityPlot in polar coordinates (solution to 2D wave equation in polar ...
261 views

### Arguments to If[] are not evaluated

I got bitten by the following: f[x_] := 3*x; g[x_] := If[Log[f[x]] < 0, f[x], 0]; g[x] Out[11]= If[Log[3 x] < 0, f[x], 0] where I thought the call to ...