0
votes
1answer
108 views

Is there such a command like FindZero[f[x],{x,1}]?

I´d like to find the zeros of a function. I know I could find them by Solve[f[x] == 0, x] but that gives me only the x-coordinates. I want to get both the ...
8
votes
2answers
318 views

About an infinite product

I have a curiosity as regards the infinite product below. I wonder why Mathematica v.8.0. says the limit is $1$. This is not true. ...
4
votes
1answer
213 views

How to transform a DumpSaved .mx file to .m file conveniently?

I have many DumpSave-d .mx files under a directory. They are generated under Linux. The .mx ...
3
votes
1answer
130 views

How can I export definitions of several symbols to a single file?

the problem related to this question What I want to do is to Export definition of several symbol into a single file. The reason I choose ...
2
votes
1answer
834 views

How can I plot a hyperbola from its complex representation?

How can I plot the hyperbola represented by the following complex equation: $$\left|z-a\right|-\left|z-b\right|=2t\tag{1}$$ Should I convert (1) into the following form? ...
0
votes
3answers
2k views

How to fix vertical axis scaling across multiple plots?

I have a collection of plots, all of which have the same horizontal-axis range, but different vertical-axis ranges. These ranges differ not only in the absolute locations of their maxima (...
4
votes
2answers
209 views

Can I make the subsection CounterBox continue counting across section boundaries?

This is what I used in a stylesheet for Section CellDingbat->Cell[TextData[{CounterBox["Section"], "."}]] This is ...
3
votes
1answer
126 views

How can I define a function taking two distinguishable sets of options?

It commonly happens that one wants to define some function foo which in turn calls some other function (e.g., Plot) that can ...
4
votes
2answers
233 views

How to add a trusted path in Mathematica for Mac?

I would like to add a trusted a path in the global preferences of Mathematica for Mac. When I go to NotebookSecurityOptions, click the tool button for ...
1
vote
2answers
222 views

How can I speed up this plot manipulation? Why does Evaluate not help?

If I were able to "Save" the computed inverse function somewhere and then plot it, the manipulation would become faster. As I understand, Evaluate should do the job, but for some reason it does not. ...
0
votes
0answers
186 views

Assigning numerical values to constants results in complex coefficients in Equations of Motion

I am using Mathematica to get the Equations of Motion (EOM) for a mechanical system (using Lagrangian Mechanics). While I get the EOM in symbolic form, on introducing the following code for assigning ...
-3
votes
1answer
228 views

NDSolve doesn't solve my system of ODEs

What is causing the error in this code? ...
3
votes
0answers
561 views

Curated data sometimes delivered in undefined units

This question may better go to Wolfram, but as it came up on the weekend, I thought I'd try here first. Take a look at the following: ...
1
vote
3answers
158 views

Equation values into list

Suppose I have a function say $f=x^2$. What I would like is a list (or even better, a list with a grid) which resembles {{1,1},{2,4},{3,9}, ...}. Ideally one should ...
1
vote
1answer
134 views

How to find best MLE using `FindDistributionParameters`

This question is an extension of this question, if we change the initial values ...
6
votes
4answers
342 views

Inserting points along a linear interval between adjacent coordinates in an array

Say I have a list of coordinates in an array {{0, 0}, {0, 1}, {1, 1}} I'd like to create a new array where, between each pair of nearest-neighbor coordinates in ...
5
votes
1answer
499 views

Why is parallel slower?

I always assumed that distributing a computation is faster, but it isn't necessarily true. When I do Sum[i,{i,10^4}] I retrieve an answer much faster then if I do ...
8
votes
4answers
569 views

NIntegrate extremely piecewised functions

I often need to integrate extremely piecewised functions, like the following one (not extreme, but gives an idea): ...
4
votes
1answer
313 views

Sporadic bug in Mathematica 7.01.0 MatrixPower and/or Eigensystem functions on floating-point symmetric matrices with repeated eigenvalues

Note: From the comments submitted below by other StackExchange users it appears that this apparent bug was fixed sometime after version 7.0.1. I asked a vague variant of this question a few days ago, ...
9
votes
3answers
570 views

Creating a simple function to compute the average of the difference between pairs of elements in an array

I have a list of the form: {{{1, 2}, {3, 4}}, {{5, 6}, {7, 8}}, {{9, 10}, {11, 12}}} How can I create a function which will take each set at the highest level of ...
3
votes
2answers
121 views

Incrementally revealing Grid (or TableForm) entries

I have a Grid (or TableForm) object like this ...
9
votes
2answers
211 views

How can I make Which format its output?

Functions like Piecewise have cool, easy-to-read formatting. In the same vein, I think it would be wonderful if the Which ...
4
votes
2answers
339 views

How to rotate 3D graphics in ListAnimate … without making a mess?

Manipulate is, of course, wonderful … but there are LOTS of examples that are simply far too computationally intensive to use live real-time animations for. In such ...
0
votes
1answer
95 views

Plotting spaces spanned by parameters

Suppose I have three coordinates functions of a vector of parameters: x[q],y[q],z[q] where q is at least a three dimensional vector in some domain Q. Is it possible to plot in 3D the space spanned by ...
1
vote
2answers
135 views

Integration leading to logarithms and chosing branch

I m doing this interal with Mathematica Integrate[(((1+b*t)^2)t)^(-1),t,Assumptions->b>0] what I get back is ...
27
votes
0answers
425 views

What Mathematica features and idioms have $n^2$ complexity or worse

Here are a few: AppendTo[data, elem], Sort[data, test], in some cases use of ___ (as ...
3
votes
2answers
135 views

Restrict MousePosition to specific Graphics object

I have a problem using MousePosition. I want to restrict the value returned by MousePosition to a specific Graphics object. ...
3
votes
1answer
417 views

why mathematica outputs “TRUE” sometimes in outputs that are conditional to mean “in all other cases”?

consider this simple Input: Probability[g <= m && m <= -g + 1, {m, g} \[Distributed] UniformDistribution[{{0, 1}, {0, gg}}]] which generates a ...
2
votes
3answers
303 views

Changing the Actions in EventHandler

I would like to be able to change which action specified events take depending on some condition. For example, I have established a SetterBar ...
3
votes
2answers
527 views

Matrices and polynomials: MMA 8 vs. 9?

I want a function to take a polynomial from a list, plug a certain matrix T into that polynomial, and return the answer as another matrix. My program uses the applyPoly function suggested by a user in ...
1
vote
1answer
153 views

Exporting a plot without drawing it

I'm trying to create a rather big 3D image and export it. Currently, I create the image then display using Show, then use ...
4
votes
2answers
2k views

Reinstalling Mathematica home edition with new linux distro

I bought Mathematica home edition and installed it under Ubuntu. During an Ubuntu upgrade the power went out and wrecked the process. I installed Linux Mate Debian Edition and tried to reinstall ...
2
votes
1answer
200 views

Differential operator involving permutations

I would like to construct an operator in Mathematica of the following form, $$D_i=\partial_i +\sum_{i \neq j}^n\frac{1}{x_i-x_j}p_{ij}, \quad i=1,...,n$$ where $p_{ij}$ is a (symmetric) permutation ...
3
votes
1answer
301 views

How can I make ArrayPlot use one pixel per plot point? [duplicate]

If I ArrayPlot an {1200,1600} matrix, the result is a plot with ImageDimensions of ...
1
vote
3answers
455 views

Adjusting the pixel values underlying a morphological component when computing an “IntensityCentroid”

When calculating an "IntensityCentroid" with ComponentMeasurements, i.e. for an image $I$ and set of components $C$, ...
0
votes
0answers
55 views

Degeneracy problem at the start of a series expansion

I am facing the following problem : I have an equation which could write $$ F(x_1(Y))-F(x_2(Y)) = 0 $$ $x_1$ and $x_2$ are the largest and smallest roots of a cubic equation; their definition ...
8
votes
1answer
597 views

Importing Excel Spreadsheet containing Array Formulas

Has anyone had any success with importing an Excel Spreadsheet holding an array formula into Mathematica? The Syntax I'm using is ...
4
votes
1answer
77 views

Why selecting text in my notebook become abnormal?

Selecting text in one of my Notebooks becomes abnormal. Here is the unselected text: and here is the partly selected text: When the text being selected, it should be like this: What is wrong ...
9
votes
2answers
841 views

Import tweets from Twitter

Robert Raguet-Schofield in the Mathematica Blog introduced a way to import tweets from Twitter into Mathematica. I attempted to use this method. I started with this line of code: ...
2
votes
0answers
86 views

Can I make V9 prompt witb “In[1]:=” before I enter an expression? [closed]

Using an older version of Mathematica, I was used to the system automatically beginning each notebook line with In[1]:=. All I did was enter the expression and ...
6
votes
5answers
219 views

Multiple level lists

Let there be a list, Sample={{{1, 2, 3}, {a, b, c}}, {{2, 3, 4}, {d, f, g}}} I want to go to individual sublists and do some operation on it.I tried a few things ...
0
votes
2answers
360 views

Autonomous equations' critical points and eigenvalues

I have three-dimensional autonomous equations and want to find their critical points and corresponding eigenvalues. They have 6 critical points each. x, ...
2
votes
1answer
347 views

3D arrow tail properties

I would like to use VectorPlot3D to plot a vector field with 3D arrows: ...
3
votes
1answer
151 views

How can I improve my Zooming code?

I recently started to work with the EventHandler function to make it possible to Zoom, Pan, etc, with only the use of a mouse. I have found a way to zoom that is ...
0
votes
2answers
209 views
3
votes
2answers
338 views

Converting inequalities to intervals

I have an inequality, ie: 1.57116 < g < 14.1405 There will be a large set of similar inequalities, and I want to find the intersection of them all. I figured it would be easier to convert the ...
3
votes
1answer
122 views

How can I avoid this ReplaceAll trap? [duplicate]

I am having some difficulties with the ReplaceAll function. When I write: {1, 2, 3, 4, 5} /. x_?OddQ -> x^2 I expect: ...
11
votes
4answers
577 views

How can I find all values of $m$ such that my cubic equation has three different positive solutions?

I want to find all the values of $m$ such that the equation $$-m^3 + 2 m^2 x + (-2 m - 1) x^2 + m + x^3=0$$ has three different positive solutions. I tried ...
29
votes
2answers
856 views

Is there a name for #1@#2&?

Why does the pure function # @ #2 & have no name? I'm asking because sometimes I find inelegant to write expressions like ...

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