All Questions

111 views

How can I execute a sequence of statements interactively?

I'm fairly new to Mathematica. Suppose I have the following function: f[x_Integer] := Module[{y, z, r}, y = 5; z = 10; r = x + y + z; r ]; and I ...
551 views

WaveletScalogram in polar coordinates

For given dataset data = Re[Zeta[1/2 + I Range[0, 100, 0.01]]]; It is nice that Mathematica can plot data in both Cartesian and Polar coordinates. ...
249 views

Change values in string under condition

how to change the width and height in the HTML code into some other values decided by ratio and a fixed width? The background is that you can adjust a image in ...
100 views

HoldForm and RandomChoice

I'm trying to get random expressions displaying. For that, I'm starting with addition, multiplication, substraction and division. When trying out this code ...
3k views

Implementing a dictionary data structure

As one learns from a course on data structures, hash maps or dictionaries can be efficient when applied to appropriate tasks. I need a hash map in Mathematica and I've never found it. I'm scratching ...
204 views

Need better font control [duplicate]

Generally many programs have a menu item to raise/lower current font size. This is much more convenient than trying to root around in in internal mathematica options. I need to change ALL default ...
512 views

Do Mathematica notebooks include personal metadata?

I am about to send a Mathematica notebook to someone and I would like to make sure it does not contain any information that could personally identify me. I would also like to produce pdf files from ...
307 views

Clearing memory of a subkernel in a Do loop

I have a Do loop, which saves data directly to a .txt file. However when I leave it running for long periods of time the RAM ...
314 views

LogPlot of the calculated data in For Loop in Mathematica

I have the following loop, for calculating a data for different values of inputs. How I can plot the result at the end of For loop? Its not matter if the plot is inside or outside the loop, I just ...
628 views

plotting the solutions of system of differential equations [duplicate]

The following code include the system of differential equations: ...
94 views

Strange response with dynamic texture and MousePosition

I built a cubic, then use MousePosition together with GUIScreenShot to take a floating region with fixed size (200*200) on the ...
97 views

How to make a function work on symbols in a specific context

Let us say we have two sets of symbols $(x, y, z)$ with the same names that live in two different contexts: ...
412 views

SparseArray row operations

Given a large (very) sparse matrix, A, how can I efficiently "operate" on only the nonzeros in a given row? For example: For each row in A, generate a list of column indices that have a magnitude ...
322 views

Sort a list of coordinates by frequency from first component of each coordinate

The situation is that I have a List like this: ...
123 views

Indicating the axes [closed]

I want to scale the $x$ axis of the plot by $x^0$ and the $y$ axis by $\tan x$. Is this possible ? Plot[Tan[x], {x, 0, 10}, PlotRange -> Automatic] EDIT: ...
2k views

How to visualize Riemann surfaces?

In WolframAlpha we can easily visualize Riemann surfaces of arbitrary functions, can we plot the Riemann surface of an arbitrary function using Mathematica and ...
216 views

Do any users know of methods to capture Twitter feeds and subject them to analysis? [duplicate]

I would like to use the output of about 300 Twitter sources and would probably collect 30 minutes of tweets at a time and subject each collection to analysis; ideally this process would be automatic ...
117 views

FindEdgeCut with weighted graphs

If I want to find a minimum cut between two nodes in a weighted graph, I would use FindEdgeCut as follows: ...
463 views

Adding/deleting weighted edges to a weighted graph

How can I add and delete weighted edges in a weighted graph? Using Graph in Mathematica I want to add a weighted edge to a weighted graph. The problem is ...
84 views

Is it possible to use the Export[] command and add another address other than the usual Home directory that is used?
69 views

Extending listability to coordinates [duplicate]

I noticed that one can subtract a since real number value from all elements in an array by writing something like {5, 4, 3, 2, 1} - 5 which outputs ...
208 views

Are there built in functions to perform a geometric transform to rotate a set of points around an arbitrary point?

I have a list of points {{4,5},{6,7},{9,8},...} in two-dimensions. I'd like to rotate these points some number of degrees $\theta$ around an arbitrary anchor point ...
449 views

Specify values for X-axis and Y-axis ticks and control their format

I have following problem: I want to set the values for the X-and Y axis by myself, but the values (e.g. 0.800) are not plotted as I defined them (see image 0,8), mathematica removes the zeros. ...
406 views

How to pick a solution from a list of solutions using a test?

I have a list of solutions that depends on a parameter b3 and I'd like to get the solution for which the x value is minimal when ...
213 views

Separating disconnected graph objects without losing vertex coordinate assignments

Say I have a graph Gtest, which has multiple disconnected components. I found that I can isolate individual components while retaining vertex coordinate ...
129 views

FindHamiltonianCycle is not invariant to edge permutation

Bug introduced in 9.0.1 or earlier and fixed in 10.0 Found this bug-like behaviour today: if the order of edges is changed so that VertexList does not return the ...
36 views

Parsing output from FindHamiltonianCycle to recover an ordered list of vertex positions for a discovered path

After applying FindHamiltonianCycle to a graph, one generates output that looks like the following: ...
107 views

StringForm and NotebookWrite

I'm trying to get my head around NotebookWrite for the last few days. I can't understand why ...
419 views

Generating a graph object where vertices are pixel coordinates and edges represent two pixels being in the same Moore neighborhood

I have a list of integer pixel positions, pts, and I wish to create one or more graph objects where vertices at these pixel positions share an edge if they are ...
1k 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. ...
202 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 ...
259 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 ...
266 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 ...
125 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 $PA = LU$, $LU$ ...
129 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 ...
2k 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 ...
2k views

Numerical differentiation methods

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

Manipulate graphs in 3D

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

Exp of big negative numbers [duplicate]

I noticed that Exp have a strange behaviour with big negative numbers ...
398 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 ...
235 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 ...
76 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, ...
416 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 ...
298 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 ...
319 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 ...
68 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: ...
372 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 ...
237 views

Dsolve too slow — is there anyway around?

I am trying to solve: ...