# All Questions

956 views

### How to extract data from contour plot as a text file?

I have the following expression from which I want to extract data for a contour plot. ...
153 views

### Generating a list of contour pixels for a morphological component

I have a set of pixilated shapes, and after transforming each shape into a morphological component, I want to be able to return the coordinates for pixels that lie on the contour of the shape. More ...
232 views

### How to find the numbers $a$, $b$, $c$, $d$ of the function?

I want to find four numbers $a$, $b$, $c$, $d$ of the function $f(x)= \dfrac{a x + b}{c x + d}$ satisfying the conditions $f(-6)=4$, $f(-5)=5$, $f(1)=3$ and $f(2)=2$. I tried ...
230 views

### How to fill between abscissa values?

How can I produce a fill (in a plot) that extends between two given abscissa values, and "infinitely" in the ordinate direction? (Of course, here "infinitely" just means "up to the top and bottom ...
101 views

### Matrices and Upper / Lower Triangular Factorizations

Does anyone know (I have searched documentation, online and MathSource) if there are ways to coax out the following factorizations from Mathematica? $A = LU$, $LU$ factorization $PA = LU$, $LU$ ...
108 views

### How to preserve focus on InputField after Print?

If you press Enter in the example below it should become clear that test is being adding to the textbox instead of the current ...
1k views

### How to keep markers as dots in a joined ListPlot?

Consider the following typical interactive sequence. First I produce a ListPlot: OK, not bad, but I want those dots to be bigger, and also joined. First, I ...
1k views

### Numerical differentiation methods

Is it possible to write a code in Mathematica that implements various differentiation methods (like forward, central, extrapolated, etc.)?
251 views

### Manipulate graphs in 3D

Is it possible to Manipulate Graphs (e.g. a ...
154 views

### Exp of big negative numbers [duplicate]

I noticed that Exp have a strange behaviour with big negative numbers ...
298 views

### How to disable differential styles/markers/etc. for multiple entities?

For functions that can produce multiple "style-able" entities, Mathematica by default will give each such entity a different style. Similar conventions apply to other features, either by default, or ...
199 views

### How to construct tuples with a given order?

How do I create a list of tuples with an ordering imposed on them, where each element is from a generating set? Specifically, I'm trying to create a listing of tuples $(x_1, x_2, ..., x_n)$ such that ...
68 views

### NotebookWrite an expression

I'm trying to write a notebook from the kernel, so using one list of elements in one document, I'd like to create a second document with some interactions between the elements of the list. For that, ...
326 views

### How to extract Audio Record data form Sound[SystemDialogInput[“RecordSound”] ?

When I set parameter "SoundReg" to collect Audio Steaming data - it's working After that I use Button$"Record"$ In my ...
249 views

### How to make Mathematica try harder to perform symbolic comparisons?

(I suspect this question is a duplicate, but I didn't find a sufficiently similar question with an answer to it.) I'm having trouble with comparisons of symbolic ...
258 views

### Is there a way to parallelize the convolution component of EdgeDetect?

Provided an image like - test = Import["http://upload.wikimedia.org/wikipedia/commons/d/d5/Sunflowers.jpg"] We can run ...
62 views

### Understanding the discrepancy between txt file import and export times, and possibly speeding up Import

I attempted to import a very short .txt file string using the Import command: ...
286 views

### How can I create jpeg images of a given file size?

Cross-posted at Wolfram Community I would like to have a function makeJPG[megabytes_] that generates random jpg images of given file sizes with itf filesize (in megabytes) watermarked on the image ...
192 views

### Dsolve too slow — is there anyway around?

I am trying to solve: ...
931 views

### How can I transfer mathematical expressions between Mathematica and Maple?

Is there a simple way to copy mathematical expressions between Mathematica and Maple (or at least in one direction)? I mean only expressions built from numbers and predefined mathematical functions, ...
126 views

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198 views

### Manipulate executes expressions multiple times

I am using Manipulate for a rather intricate front end for data visualization. I was getting very sluggish performance and was able to boil the problem down to a ...
160 views

### HoldForm[Operator ##] on some list

Recently in response to this question Mr.Wizard suggested an unusual way to summing numbers. This doesn't seem to be documented. ...
163 views

### Builder pattern for complex objects construction

Intro I was watching "UnRisk-Q Instrument Builder" talk (https://www.youtube.com/watch?v=Xx3goIBpOdE) and those guys use builder pattern to build complex objects like this: ...
260 views

### Modelling the effect of a structure on a “tsunami” (hyperbolic wave equation)

So, the hyperbolic wave equation can be quite easily solved in Mathematica like this: ...
164 views

### Complex surface: Finding the perimeter of the union of multiple disc intersections

Consider a system of $N$ circles($N>40$) Each of radius $5$ and the center of these circles along a circle at origin of radius $3$ [as given in code]. Code for above description :- ...
180 views

### ArcTan and Compile

See following three snippet code: ...
57 views

### Setting OperatorSubstitution to false causes Plot's labels of sufficiently small size not to appear in the specified typeface. Is this a bug?

If I set OperatorSubstitution to False, the labels of Plot will not use the typeface ...
264 views

### Export list elements each to it's own page in a multi-paged PDF document

I have a list, myList, of let's say 20 (different) objects myList = Table["object", {20}] I know would like to export every ...
706 views

### How to find the distance of two lists?

I have two lists as the followings: ab = {1, -1, -1, -1, 1, 1}; ac = {1, -1, -1, 1, 1, 1}; How I can find the difference (more precisely, the edit distance) ...
40 views

### How to get .cdf format to work with functions? [duplicate]

I would like to create simple functions and then pass them into a Manipulate function that can be used in a .cdf file. eg ...
175 views

### Efficiently determining if a morphological component overlaps a polygon with vertices at real number coordinates

I have a list of morphological components $m$, a set of vertices for a polytope $P$ (at real number coordinates), and I'd like to be able to calculate a list of morphological components $m'$ that ...
2k views

### Position of axes labels

I have a 2D parametric plot like the following: ...
1k views

### Guidelines on giving readable names to variables [closed]

I know that one cannot use underscore to a variable name, like degree_of_The_First_Polynomial. But for a long variable name, it ...
172 views

### How can I use Dynamic to run a script when a new file is added to a directory?

I have an external program saving files to some directory on my hard disc. I'd like to run a script that imports and runs a script on each file as it is added to the directory. Is there a simple way ...
193 views

### How to get Cases to wrap results in an arbitrary head?

A number of functions provide for results to be wrapped in an arbitrary head. This is very important in cases where the results should not be evaluated. Take ...
316 views

### Faster Eigenvalues with lower precision goal

I compute all eigenvalues of a large matrix, and I decide that the speed is more important than the precision. Then the question is, can I speed up Eigenvalues[] by ...
48 views

### Phase Unwrap List Of Points: Implementing continuous phase/Arg function for List of Points [duplicate]

I am looking for a function to unwrap phase of a list of points as done here for the continuous case. I have the Re/Im data as my input and would like the unwrapped phase as the output. Does anyone ...
389 views

### Chart illustrating options that affect Graphics/Graphics3D objects

In Mathematica there is a seemingly never-ending list of parameters that affect the appearance of Graphics and Graphics3D ...
122 views

### How to use MacPorts' gcc with CreateLibrary?

Short version: What's the simplest way to use MacPorts' gcc with CreateLibrary? Long version: CreateLibrary uses ...
269 views

### Find integer values of p such that $(2^p - (2^2)(3^2))/ (3^3)$ is an integer

Find integer values of p such that $(2^p - (2^2)(3^2))/ (3^3)$ is an integer.
123 views

### Text with specified FontSize looks smaller than expected

The simplest way to see what the post's title is trying to convey is to evaluate: ...
158 views

I'm grading for a class using Mathematica right now, and one of the students ran into a weird issue. When he ran code like this: ...
797 views

### How to get and set default font parameters for Plot, ListPlot, LogPlot, etc.?

How can I find the default font parameters (family, size, etc.) for the text that appears in Graphics produced by Plot, ...
96 views

### How do I type boxtimes?

How do I type boxtimes in Mathematica, for example $a\boxtimes b$? This symbol is used a lot in mathematics, but I found no corresponding part in Mathematica. In TeX form, I can type \boxtimes. Can ...
442 views

### A faster way to do sums?

I found out that,it is INCREDIBLY(like 100 times) faster to use Dot instead of Sum,to perform long sums. But I have not been ...
156 views

### Hold expression with RandomInteger

One more question for today: I'm trying to show two random integers with a plus (+) sign between them, in an unevaluated form. I know how Hold and HoldForm work, but they hold everything, including ...
261 views

### How to determine numeric equivalent of Tiny, Small, etc. image sizes for Graphics?

Is there a way to find the numeric equivalents of Tiny, Small, Medium, and ...