# All Questions

781 views

### Linear regression with x and y errors

I have a question about finding a linear regression weighted with x and y errors. I found the answer provided by 0x4A4D in Estimate error on slope of linear regression given data with associated ...
143 views

### How to evaluate only arguments, but leave topmost expression unevaluated? [duplicate]

I want to represent expressions mostly in unevaluated form, but being able to evaluate it's subparts. For example, how to evaluate only arguments, but leave topmost expression unevaluated? For ...
36 views

### Eigenvalues for large matrices without Root-Solution [duplicate]

I read some other questions and tried to implement the given answers but yet, I did not succeed to find proper solutions for my eigenvalues. I hope someone can show me how to do this for this case, ...
230 views

### Unresolved differential equation [closed]

Why can't Mathematica solve this equation as stated? ...
2k views

### Visualization of Bivariate Distributions

I know it is perfectly possible to show the bivariate probability distributions in MMA. But my question is can we show each dimension of distribution in 2D dimension while we are showing the 3D plot? ...
384 views

### Is it possible to define custom compound assignment operators like ⊕= similar to built-ins +=, *= etc?

I would like to do something like this: ...
45 views

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550 views

### Image Processing: Concrete test blocks

Background Concrete is mixture of aggregates and cement. Aggregates are composed of different sizes and colors. Core samples are taken by drilling in order to test the strength of concrete . They are ...
127 views

### Non-Solvable PDE?

I would like to know whether this PDE is solvable and if yes, for which values of $a$. ...
508 views

### Share experiences, preferably the surprising ones, with using ItoProcess

Can people please share their experiences, preferably the surprising ones, with using ItoProcess? I am a big fan of ItoProcess and have already used it for several finance-related tasks, though I ...
425 views

### Performing Computations on Sets

I would like to find a permutation of $\quad S=\{\frac{1}{10}, \frac{1}{2}, \frac{4}{7}, \frac{3}{5}, \frac{2}{3} \}\quad$ that maximizes the sum of theses elements raised to unique powers: ...
149 views

### Integrating and plotting pde system solution

I have a trouble with plotting a pde system solution. I'm solving a PDE system in 2-dimensional space and then I want to integrate the solution along one dimension and build a log plot along the ...
512 views

### RLink and R v3.0.1?

Running InstallR["RHomeLocation" -> "C:\\Program Files\\R\\R-3.0.1"] results in a popup box titled "Version Mismatch" saying Error: R.DLL version does ...
654 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 ...
112 views

### How can I revise my program to avoid “No more memory available”? [duplicate]

I have a program for calculating a type of list. ...
273 views

### InputField with Scrollbars [duplicate]

Edits are marked in bold: How do I make an InputField that behaves just like the following HTML Textarea example. ...
177 views

### How to convert comment in RowBox to DisplayForm string

ToExpression[RowBox[{"a","(*","what", "*)"}],StandardForm] This conversion above ignores the commment content (*what*) The ...
521 views

### Improve TextRecognize[] on numbers

I have an image contain only numbers, and TextRecognize fail to recognize some numbers: img=; TextRecognize[img] (*826718*) The documentation says that "The ...
459 views

### Summation with constraints

I am trying to do the summation shown below, $\sum_{i_1=0}^{imax_1} \sum_{i_2=0}^{imax_2} \dots \sum_{i_k=0}^{imax_k} f(i_1,\dots,i_k)$ $k$ is a variable. Therefore $i$ and $imax$ are defined as ...
131 views

### Simple Macro or Meta Programming for Data Analysis [duplicate]

I have a large number of data variables that are represented in MMA as symbols set to lists. For example: x = {1, 2, 3}; y = {4, 5, 6}; I want to be able to ...
113 views

### DateListPlot input entry problem

I imported some data from Excel and got the following for my date and values: {{{1986, 1, 2, 0, 0, 0.}, 25.56, ""}, {{1986, 1, 3, 0, 0, 0.}, 26., ""} It seems ...
111 views

### NMaximize with matrix input

I defined function f[x_, fixed_] := {...}. Here x is an $M\times N$ matrix. I want to maximize $f$ with respect to $x$. I have ...
55 views

### Animated 3D graphics is low resolution [duplicate]

I'm trying to animate a 3D shape in Mathematica 7. It's working, but the graphics is extremely crude while animated. The resolution gets better if I stop the animation. Is there a way to get a nice ...
508 views

### Derive a smooth circle with cusp from an image

question 1 get the center (sample data) sample is the black circle with cusp. ...
60 views

### Color of numbers and defined functions [duplicate]

How do I change the color of numbers and the text representing defined functions in my notebook?
133 views

### How to export to .html .nb file together with links «in» and «out»

If use «File > Save As > HTML» links «in» and «out» are lost How to save a document without loss of these lines/links? UPD: You can write in the css rules (...
1k views

### Find radii of concentric circles in image

I have an image of concentric circles, I would like to find the radii of the circles (only the innermost few are important). I've had a go using what I could find in previous posts, but am a bit ...
168 views

### Importing Data with Line feeds

I am trying to import data from a CSV file into Mathematica that contains line feeds in certain elements that I wish to be properly rendered in Mathematica. I suppose this has something to do with the ...
187 views

### Effect of Block[] on iterators in Manipulate[]

The following is a toy example that hopefully shows the problem clearly enough. Why does the following code create a nice, manipulable output: ...
406 views

### Adapting “Find and Replace” functionality to work with Patterns

I was thinking if there is something like Find and Replace (Crtl+F) functionality adapted to work with patterns. Probably not, but it seems possible to create this with some effort and skills in ...
620 views

### How to simulate the response of a linear parametric varying system in Mathematica?

Consider the following system \begin{align} \dot{x}(t)&=\sum_{i=1}^{2}\rho_{i}(x(t))\left[A_{i}x(t)+B_{i}u(t)\right]\\ y(t)&=Cx(t) \end{align} with: ...
181 views

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840 views

### Fixed color scale in multiple density plots with Fixed PlotLegends scale

From the great answer of Mr. Wizard, I would like to learn how to implement the associated PlotLegends scaled too. Here is the simplest example with PlotLegends, which does not look to be scaled: ...
206 views

### Exporting multiple arrays in a single HDF5 file in Mathematica 7

Bug introduced in 7.0 and fixed in 8.0 I am using Mathematica 7 and I need to export a table of data and the corresponding x and ...
610 views

### How to graph a series of coupled oscillators and watch the wave move along them

Here are the differential equations that set's up the 11 coupled oscillators. ...
281 views

### How to apply a free-form input Function using InputField

I am trying to take a free-form input Function to create a list using NestList. ...
460 views

### InverseFunction on an Interpolating Function is misbehaving

I am getting strange behavior when I try to calculate the inverse of an interpolating function for two similar data sets. My data sets are: ...
1k views

### How to label axes in 3D plot adequately?

The following code produces plot with axes labels, which are jumping constantly. ...
45 views

### 3D plot changes it's size while rotating [duplicate]

When I am rotating drawn 3D plot by mouse it rotates Ok until mouse release. After that it slightly changes it's size instantly. Probably it tries to accommodate document layout or something. Is it ...
137 views

### Forming product of function of prime factors

Given a list of numbers each containing 2 prime factors, I wish to make a list of the products of the logs of each factor. For example, given L = {4,6,9}, I would like to form P = ...
366 views

### Unexpected result {“.a”, “co”, “.m”} from Sort[{“.m”, “.a”, “co”}]

I came across the following situation: Evaluating Sort[{".m", ".a", "co"}] Results in {".a", "co", ".m"} I wondering: ...
248 views

### Pattern definition for replacing plus and subtract

Suppose I have two functions $h_1(x)$ and $h_2(x)$, for which we know their sum and their difference: $$h_1(x)+h_2(x) = d(x) \qquad h_1(x)-h_2(x) = i f(x)$$ I have a complicated expression, in ...
870 views

### White spots in ListDensityPlot

I have a problem with ListDensityPlot. I have some data on an irregular grid. I try to plot them with ...
102 views

### Recurrence equations with periodic coefficient

Suppose I have the following recurrence equation: $$F_{i+1}P_{i+1}+F_iP_i-P_{i+1}+P_i=2J\,, \quad\textrm{with}\quad F_{i+L}=F_i,P_{i+L}=P_i\,.$$ $J$ is constant, $\{P_i\}$ are probabilities with ...
1k views

### Digital filter of image in Fourier space

Consider the contour plot below, of a function f(x,y) - which is calculated numerically by solving some equations. If one looks carefully, one can observe two types of waves, to the left and right of ...
298 views

### Write a function using pattern test to test whether the input is polynomial and print error message if not

I am doing this which is supposed to be an easy problem and which I think my code should be correct but for some reasons it is not working. May anyone help correcting my mistakes? How should I write ...
710 views

### Plotting rainbow circle [duplicate]

I am trying to plot a parametric circle in rainbow colors. It should go round once, but I'd like to be able to make it go round the rainbow an arbitrary amount of times. I currently have: ...
577 views

### Find elements of a list which are empty

Sorry for the most basic of questions. How would I find the positions of a list of elements which are empty, for example I have the list ...
So I need to use Mathematica to find the solution of $y=x- \epsilon \sin(2y)$ as a power series in terms of $\epsilon$. I'd assume I'd need to create an equation $f=x-y- \epsilon \sin(2y)$, then ...