7
votes
1answer
238 views

How do you use SystemsModelFeedbackConnect?

I'm trying to grasp the new control system functions in Mathematica 8. I'd like to connect a controller model to a model of a plant to simulate the behavior of the system. I define a simple servo ...
9
votes
2answers
277 views

How to find a specific error message?

Is there a way to find an existing error message in the System` context, that is used for a certain case? I want to include a message in a custom function that ...
4
votes
3answers
754 views

How to find all graph isomorphisms in FindGraphIsomorphism

I found the second definition of the function FindGraphIsomorphism not working. Here's the definition Mathematica 8 gives: ...
0
votes
1answer
342 views

How can I make many runs of a simulation and plot all the results with one expression evaluation?

I have many cells, starting with this first cell: ...
6
votes
1answer
519 views

Placing Manipulate controls in multiple columns

I have a Manipulate construct with a square Graphic on the left side and all the controls placed on the right side. There are so ...
7
votes
2answers
297 views

Compiling a spatial predator-prey model and optimising it for speed

I just made a spatial predator-prey model but it runs a little slow and I am seeking some advice on how to compile it to optimise it for speed. I first define matrix with 0 for an empty site, 1 for a ...
4
votes
1answer
154 views

Issue with setting up docked cells

Normally I try to stay away from asking RTFM- questions but concerning docked cells I am currently groping in the dark. The documentation examples tell me how to create a new window containing a ...
3
votes
1answer
316 views

Errors in Compile

I defined a function ...
2
votes
1answer
395 views

Use output from Plot3D as an object in Graphics3D that I can transform

I'm trying to draw up an optical system where I can show an example of wavefront error on an exit pupil. It would be great if I could take the results of a 3D function from Plot3D and use it as a ...
2
votes
3answers
342 views

Notification sound when simulation done? [duplicate]

Possible Duplicate: Customize front end to add notifications when evaluation finishes? How to setup sound alert notification when simulation is complete? I need to do something else while ...
1
vote
1answer
681 views

Use selfdefined ColorFunction to encode z dimension with predefined limits

In my last question we defined a colorfunction cf. Now I want to use this ColorFunction for a number of different plots (...
6
votes
2answers
297 views

Exporting BarChart3D as PDF produces artefacts

So I think the following image already shows the problem, similar to Avoiding white lines inside filled area in RegionPlot exported as PDF or PS the pdf export of the chart creates thin lines in the ...
4
votes
2answers
722 views

Define a color function based on color samples obtained from ColorBrewer

I am quite new to mathematica and I am searching for a way to create a smooth colormap based on the samples given by http://colorbrewer2.org/ . Is it possible to create a interpolated function from ...
3
votes
4answers
1k views

how to draw a moving point on a curve?

I almost remember an example that has a moving red point on a given curve, which will moving time and time again, with no controls... now, here is my question: given a curve by ...
4
votes
2answers
324 views

BarChart with BarOrigin->Left: axis on top

This question is somewhat related to this one. Let's say this is the BarChart i want to make: ...
6
votes
1answer
386 views

Find the list of weather stations for specified cities

I wrote some code which retrieves temperature data from three cities every hour for five days. My problem is that the default station from which WeatherData[] gets ...
2
votes
2answers
394 views

Eigensystem, Eigenvalue doesn't output nonreal eigenvalues

Basically I have a matrix and when I used either Eigenvalue or Eigensystem, it doesn't output nonreal eigenvalues, instead it ...
7
votes
1answer
324 views

Anyone recognize this heatmap? [closed]

Anyone know the origins of the attached heatmap/daylight overlay? I see it on the Mathematica homepage all the time and I even saw it once on Wolfram|Alpha launch video. I know there are ways to ...
3
votes
1answer
283 views

Why can't Mathematica parallelize this?

The following code makes mathematica print "ParallelTable::nopar1: [...] cannot be parallelized; proceeding with sequential evaluation." ...
5
votes
3answers
663 views

ColorFunction and/or ColorScaling issue with ParametricPlot3D

My goal is to use ColorFunction to color a cylinder based on the $z$ value of a separate Plot3D. I'm not sure if I am making a ...
4
votes
6answers
255 views

Sorting Matrix elements

I have matrix in as shown, consisting of real numbers and 0. How can I sort it to become out as shown? ...
1
vote
1answer
128 views

How do I find the value of specific printing options?

I'd like to programmatically save (and then temporarily change and restore) specific printing options. I get as far as Options[Notebook, PrintingOptions] but ...
10
votes
3answers
335 views

Typeset unbalanced brackets

In LaTeX, you can typeset expressions containing unbalanced brackets, by balancing them with an invisible delimiter \left. or ...
4
votes
1answer
315 views

Can Mathematica check spelling during typing?

I can't see a way to get Mathematica to check my spelling as I type. Is this feature not supported? I've done everything I can think of with my options: Is there a setting I'm missing?
9
votes
5answers
619 views

Create filling between two trig functions

Working with trig functions, period, amplitude, etc. I found a worksheet at a calculus website, with some nice questions related to interpreting trig functions, at least, they provide some "fun" ...
7
votes
2answers
188 views

Why isn't Simplify doing more simplification of this expression?

When I try this Simplify[(1-a)*(1/(1+x*m))^(1-a)(1+m)^(1-a) + (1-a)*(x*m)^a*((x*m)/(1+x*m))^(1-a)*(1+m)^(1-a)] the output is $$\frac{(1-a) (1+m)^{1-a} ...
1
vote
0answers
242 views

Return Functions from parallel execution of module

I wrote a module which numerically solves an ODE using NDSolve. The result from this is e.g. either ...
7
votes
3answers
340 views

Operations on elements of ragged lists

Suppose I have a list of lists with different lengths, sorted from longest to shortest ...
0
votes
1answer
105 views

Defining functions from expressions of variable lengths

I have a list of symbols that I have defined using d = Table[Symbol["d" <> ToString[i]], {i, 1, n}] giving ...
5
votes
5answers
1k views

How to group certain symbolic expressions?

For example, I have the following expression : A( 2 x1 + B(y1 + y2) + 2 x2 ) How do I make the output look like this (grouping ...
10
votes
2answers
299 views

Dependent Manipulate sliders

I would like to use dependent sliders in Manipulate. First slider K0 should be independent and varied from ...
16
votes
1answer
444 views

Speeding up trigonometric integral

Context On a possible non trivial toric topology for the Universe (nothing less!). Problem I would like to carry out the following integral for $\ell=2,4\cdots 20$. $$\int _0^{\pi }\int _0^{2 \pi ...
1
vote
1answer
123 views

Working of Date[]

Date[] returns the current date of local system, Date[1] returns {2012, 11, 15, 17, 41, 0.3161629}, ...
1
vote
3answers
108 views

Timing display of Graphics (Front End timing)

I want to know how much wall-time it takes to display a Graphics For example this one: ...
5
votes
3answers
479 views

How to sum matrix elements based on finding the first (and second) non-zero elements of each row?

I have a matrix: I would like to sum all the first non-zero elements of each row so that I get a value of $$25.5317 + 8.85471 + 6.90018 + 32.9436 + ... $$ and so on and simply ignore zero rows. ...
15
votes
3answers
919 views

Monotone, periodic 1d-interpolation with continuous 1st order derivative

Lately, we had this thread about interpolation where J. M. linked two interpolation methods. The background for my question is that I estimated a parameter in polar coordinates with dependence on the ...
0
votes
0answers
35 views

Why isn't the matrix product computed? [duplicate]

Possible Duplicate: Why does MatrixForm affect calculations? I have the following input: Why is the matrix not computed, giving me a $2 \times 2$ matrix?
9
votes
2answers
799 views

Exporting data from Excel into Mathematica using clipboard

I know that it's possible to import Excel data into Mathematica using the Import command, as we can see in this post. But some times, I need just to do some fast ...
14
votes
2answers
822 views

Dealing with large files

I have a *.dat file in which the contents are basically one giant list: {1,2,3,4} {5,6,7,8} {9,10,11,12} and so on. I'd like to read in the first 500 members { ...
10
votes
2answers
365 views

Determining the default Method used in optimization and root-finding algorithms

Is it possible to extract the Method which is used in functions like NMinimize, FindRoot, ...
1
vote
1answer
243 views

How to Sort on row by row basis?

Say I have matrix how to sort on row by row basis to get:
3
votes
1answer
315 views

Plot maximum and minimum temperature of a day for range of time interval

How to display (in any graphic representation) the maximum and minimum temperatures for one city in one of these selected time periods over the 5-day period? The time periods are: Morning (06:00 to ...
5
votes
5answers
656 views

Prevent Part[] from trying to extract parts of symbolic expressions

If you have a list, e.g. {1, 2, 3} then you can extract the $k$th part using Part (...
4
votes
1answer
847 views

How to print coordinates above certain points

How do I place the x and y values of the points I have found (maxandmindistance) above the point in a plot? Here is my code so far: ...
2
votes
1answer
194 views

Difference between Map[f[#] + g[#] &, {a, b, c}] and Map[f[x]+g[x]&, {a, b, c}]

Map[f[#] + g[#] &, {a, b, c}] vs Map[f[x]+g[x]&, {a, b, c}] My question is: why is the output different? ...
11
votes
9answers
873 views

How to join each of the spheres? Or, how to make a 3D grid?

Graphics3D[{ {RGBColor[#], Sphere[#, 1/50]} & /@ Tuples[Range[0, 1, 1/5], 3] } ] It gives this: Now I want to get this one: How? As simple as ...
6
votes
3answers
171 views

Is there any way to collect only variables with a specific power?

Suppose I've got this: In[13]:= Expand[(a + b) (b + c) (c + a)] Out[13]= a^2 b + a b^2 + a^2 c + 2 a b c + b^2 c + a c^2 + b c^2 And I want to collect only ...
6
votes
1answer
318 views

Why is MapIndexed better than mapping over a range?

Background I'm working on an application in which I need to create and control two sets of locators. I know from reading the Mathematica documentation and certain posts on Mathematica.SE that this ...
1
vote
1answer
124 views

How can I use several data fields drawn from curated data at once?

How can I use "MinTemperature", "MaxTemperature", and "Temperature" properties of ...
2
votes
1answer
106 views

How do I stack a RectangleChart?

What I would like to do is represent the state of a machine over a period of time using a RectangleChart (or anything else that can do it) . The chart will need to be made up of equally sized blocks ...

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