5
votes
2answers
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. ...
1
vote
1answer
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 ...
3
votes
3answers
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 ...
2
votes
1answer
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 ...
0
votes
0answers
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 $PA = LU$, $LU$ ...
1
vote
1answer
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 ...
9
votes
4answers
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 ...
4
votes
4answers
1k views

Numerical differentiation methods

Is it possible to write a code in Mathematica that implements various differentiation methods (like forward, central, extrapolated, etc.)?
2
votes
2answers
251 views

Manipulate graphs in 3D

Is it possible to Manipulate Graphs (e.g. a ...
8
votes
1answer
154 views

Exp of big negative numbers [duplicate]

I noticed that Exp have a strange behaviour with big negative numbers ...
5
votes
3answers
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 ...
4
votes
4answers
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 ...
3
votes
1answer
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, ...
3
votes
1answer
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 ...
2
votes
1answer
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 ...
2
votes
2answers
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 ...
1
vote
0answers
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: ...
3
votes
0answers
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 ...
1
vote
1answer
192 views

Dsolve too slow — is there anyway around?

I am trying to solve: ...
11
votes
3answers
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, ...
4
votes
2answers
126 views
2
votes
1answer
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 ...
2
votes
2answers
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. ...
7
votes
1answer
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: ...
3
votes
1answer
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: ...
1
vote
1answer
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 :- ...
6
votes
2answers
180 views

ArcTan and Compile

See following three snippet code: ...
2
votes
0answers
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 ...
3
votes
2answers
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 ...
14
votes
6answers
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) ...
0
votes
0answers
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 ...
1
vote
1answer
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 ...
4
votes
3answers
2k views

Position of axes labels

I have a 2D parametric plot like the following: ...
9
votes
3answers
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 ...
5
votes
1answer
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 ...
19
votes
1answer
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 ...
5
votes
2answers
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 ...
0
votes
0answers
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 ...
27
votes
2answers
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 ...
6
votes
1answer
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 ...
-1
votes
3answers
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.
1
vote
1answer
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: ...
1
vote
2answers
158 views

Confused about scoping, not sure what to ask

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: ...
11
votes
2answers
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, ...
1
vote
1answer
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 ...
2
votes
2answers
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 ...
7
votes
4answers
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 ...
13
votes
1answer
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 ...
1
vote
1answer
176 views

Blank VectorPlot

I'm trying to draw a VectorPlot of a function that admittedly probably is not very well suited for such a plot. But at the moment I just get a white sheet and I ...
2
votes
1answer
191 views

Dynamic [ NotebookEvaluate [“_”] ]

A nice way to centralize various tasks in one notebook is the NotebookEvaluation function. For instance I can evaluate ten notebooks from a single notebook (e.g. ...

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