# All Questions

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 ...
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 ...
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: ...
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: ...
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 ...
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 ...
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 ...
316 views

### Errors in Compile

I defined a function ...
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 ...
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 ...
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 (...
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 ...
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 ...
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 ...
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: ...
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 ...
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 ...
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 ...
283 views

### Why can't Mathematica parallelize this?

The following code makes mathematica print "ParallelTable::nopar1: [...] cannot be parallelized; proceeding with sequential evaluation." ...
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 ...
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? ...
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 ...
335 views

### Typeset unbalanced brackets

In LaTeX, you can typeset expressions containing unbalanced brackets, by balancing them with an invisible delimiter \left. or ...
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?
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" ...
188 views

123 views

### Working of Date[]

Date[] returns the current date of local system, Date[1] returns {2012, 11, 15, 17, 41, 0.3161629}, ...
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: ...
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. ...
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 ...
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?
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 ...
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 { ...
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, ...
243 views

### How to Sort on row by row basis?

Say I have matrix how to sort on row by row basis to get:
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 ...
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 (...
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: ...
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? ...
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 ...
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 ...
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 ...