# All Questions

346 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 (...
278 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 ...
625 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 ...
284 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: ...
333 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 ...
382 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 ...
316 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 ...
256 views

### Why can't Mathematica parallelize this?

The following code makes mathematica print "ParallelTable::nopar1: [...] cannot be parallelized; proceeding with sequential evaluation." ...
585 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 ...
238 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? ...
116 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 ...
311 views

### Typeset unbalanced brackets

In LaTeX, you can typeset expressions containing unbalanced brackets, by balancing them with an invisible delimiter \left. or ...
270 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?
547 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" ...
183 views

120 views

### Working of Date[]

Date[] returns the current date of local system, Date[1] returns {2012, 11, 15, 17, 41, 0.3161629}, ...
107 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: ...
388 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. ...
825 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?
714 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 ...
650 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 { ...
328 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, ...
216 views

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

Say I have matrix how to sort on row by row basis to get:
270 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 ...
534 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 (...
704 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: ...
191 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? ...
763 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 ...
157 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 ...
264 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 ...
114 views

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

How can I use "MinTemperature", "MaxTemperature", and "Temperature" properties of ...
94 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 ...
274 views

### How to do conditional matrix division when elements are a combination of zero and real numbers?

I tried to divide two large matrices DLand PL of size 100,000 x 5 each and they look like this, DL= and PL= By using conditional function: ...
289 views

### Use of Cellular Automaton or Discrete Convolution to calculate Potts Energy of a 2D Matrix

In a project of Monte Carlo Modelling of Grain Growth (Link) one of the most costly subroutines is the calculation of the Potts-Energy of an Monte Carlo Grid cell by comparing the center cell value ...
132 views

### replacement rule to pull independent expression outside of Integrate

I'm trying to write a fairly general replacement rule that will pull expressions independent of the variable of integration outside of Integrate, since Simplify and ...
590 views

### How to find all roots and maxima and minima and graph them

I need to find all the roots of this function. I know it is simple to find by hand, however, I wish to learn how to do it so I can apply it later. The problem is that it only gives me one root. ...
146 views

### Function behaves differently inside a package than outside

I defined a function TestHead in a notebook as follows: TestHead[z___] := TrueQ[{z} == Cases[{z}, x_ /; Head[x] === avar]] to ...
921 views

### Filtering beat-to-beat heart rate data

From an experiment, I have a dataset of beat-to-beat heart rate data: a list of the time between each heart beat in [ms]. The data is measured using an infrared optic sensor at the finger tip. The ...
307 views

### Converting XMLElement objects to plain text

Short version: How can I convert an XMLElement that represents part of a HTML document to plain text? Long version: The more general problem is extracting ...
418 views

### An elegant way to plot a numeric function that returns a list, and have each element in a different color

I have a function that takes a numeric argument and returns a list of numbers. I want to plot each element of the list in a different color. If I use this command, ...