# All Questions

310 views

### Small Issue with Chebyshev Derivative Appoximation

I am trying to get approximate the derivative of a function from its Chebyshev expansion. I start out with the following random function ...
238 views

### Return a Part by Reference? (For accessing hierarchical / structured data)

Is there a way to return a part of a list by reference, for reading and writing? I want to do this so I can easily manipulate "rule-styled structured", i.e., hierarchical data that is loaded from a ...
795 views

### How does one draw a parallelepiped in Mathematica?

I'm a bit new to the application, and I'm not sure how to draw a parallelepiped in Mathematica.
379 views

### What's fastest way of defining 10^5 down values?

I want to define isGood[___] = False; isGood[#] = True & /@ list where list is a list of several million integers. ...
270 views

I want to be able to do high dimensional integrals like, (..naively I wrote it as this..) ...
161 views

### Comparing Unequal Lists of Surnames to Establish Over or Under-Representation

I've been using Mathematica to explore historical records. I have two long lists (one is 69k, the second 17k) of unequal length. They are like so (FWIW, the first list is the first 40 entries from the ...
364 views

### Generate a Combination of letters by a number

I'm trying to write a function f. example: ...
232 views

### Can mathematica simplify an expression setting simplified answer equal to zero?

Basically I want to reduce something like: Subscript[P, 4] - Subscript[P, 5] == Subscript[R, 4, 5]* Subscript[i, 4, 5] when only one of them is known (...
260 views

### Creating a matrix from the output of a variable inside a for loop

I would like to enter the results of the following loop inside a matrix as its elements: ...
831 views

### Is Abs[z]^2 a bad way to calculate the square modulus of z?

For a numerical quantity z, Abs[z] returns the square root of the sum of the squares of the real and imaginary parts of ...
215 views

### Debugging graphics

All the examples I am seeing on internet are related to normal functions that carry out loops and assignments but I have not seen one example where I can see a graphics based program being debugged. ...
675 views

### How to calculate FDCT

I'm new to Mathemtica and I'm trying to calculate Discrete Cosine Transformation FDCT. I found the FourierDCT built-in function, but not DCT, so I need to implement it. I have tried couple of ideas ...
513 views

### How to create a simple interface to get file path and execute some code on it?

I need to create a simple user interface to choose one file in the notebook directory, import it and execute some functions on the imported data. For the first version I created this code: ...
342 views

### Opening a notebook from command line in an existing front end instance

I am using Linux, and I would like to be able to programmatically open notebooks in a running Mathematica instance from the command line. Currently, doing something like ...
118 views

### LinearSolveFunction unusable if stored to disk?

I encounter a problem when saving a LinearSolveFunction to disk, where the LinearSolveFunction is obtained with LinearSolve for ...
761 views

### How can I make hatching filling of plot

How can I make hatching filling of plot Like this: I use another one plot with shifting to make filled area above: ...
624 views

### How can I fill-in this Pentagram?

This is my code: Graphics[{EdgeForm[Yellow], Yellow, Polygon[Table[{Cos[t], Sin[t]}, {t, 0, 4 π, (4 π)/5}]]}] which gives this: but I want to get: How?
800 views

### Export data to Excel with adjusted column size

I'm trying to export some data with formats into Excel. It works ok, but the columns size get not properly adjusted. I don't want to use some complicated solution based on this example. In my tests, ...
324 views

### Guides for programming CDFs

Are there any tutorials for programming high-quality CDFs, like the interactive calculus textbook presented at wolfram.com? Mathematica's Help is extremely impressive but it really does not help much ...
279 views

### Proving a recurrence in Mathematica

I have $$j_n=\int_0^1 x^{2n} \sin(\pi x)dx.$$ How do I show that $$j_{n+1}= \frac{1}{\pi^2}(\pi- (2n+1)(2n+2)j_n)\, ?$$ I keep getting a recurring integration by parts and I can't simplify it. ...
146 views

### How to mix Unevaluated property of function arguments with expression assignments?

This is a follow-up to my (solved) question How to distribute a generic function of two arguments (without evaluating the arguments) Say, I have a binary function ...
147 views

### Why doesn't Log[Gamma[]] simplify to LogGamma[] where it could?

I have been playing with various equations involving amount of permutations in relatively large sets. Easiest way to look at these is something like Log[10, bignumber!] . Often expressions, even ...
246 views

### Inputting two arrays for a module in Mathematica

I am relatively new to the Mathematica enviroment and not sure where I am going wrong. I have evaluated the question and understand it, but dont know how to exactly create a module for it. The ...
445 views

### Creating a package of special plots

In my work as a math teacher, I create lots of graphs to illustrate ideas. I have lots of math books and will often try to duplicate a particular style of graph. Below, one very simple example, ...
428 views

### Equivalent of Python's “all” function in Mathematica

The Python function def isPrime(n): return all(n % i for i in xrange(2, n)) checks if a number is a prime number by using ...
282 views

### How to save a web page in mathematica?

For a given web page http://www.nytimes.com/, is it possible to save it as : first: only HTML(within css) second: more elements(include pictures and so on) just like what a browser can do. ...
305 views

### Better Autocompelete for the Front-End

I wonder if it is possible to improve the front-end's autocomplete capability. Compared with some other more sophisticated editors/IDEs, such as eclipse, Mathematica's front-end does not provide a ...
539 views

### Calculating an exact orthogonal modal matrix in Mathematica

I can calculate the modal matrix of a matrix A using the command JordanDecomposition[A][[1]], and a decimal approximation of the orthogonal (or normalised) modal ...
3k views

### Local max/min of Mathematica data sets

Is there a way in Mathematica to find the local maxima of a set of points? Suppose you have ...
1k views

### Why doesn't Mathematica simplify a square root of an expression that equals a square of a positive real?

When I try and simplify this expression: ...
1k views

I have figures containing several arcs showing the extend of angular measures, and would like to indicate the directions in which angles are measured with arrowheads. How do I add an arrowhead at the ...
632 views

### Adding ContourLabels changes contour colors?

I have an array s5 I want to plot using ListContourPlot ...
225 views

### TreePlot EdgeLabeling Style

I am trying to control the style for edge labels in treeplot and have run into a problem. Consider these two graphs: ...
325 views

### With comma as decimal separator, how do you insert a period in the header/footer?

I have enabled comma as my decimal separator, which means that comma still acts normally and when pressing period it will be converted to a comma. In the header I would like to make a period, so I ...
89 views

### How to make 3d solid volume from set of images [duplicate]

Possible Duplicate: How to show solid bodies using volumetric rendering? I have a set of images, and I want to construct a z-stack, then reconstruct it to a 3d volume. My previous ...
218 views

### Numerical-Symbolical Integration (Calculus)

I created a simple numeric-symbolic integration. Here you can use symbolical and numerical techniques at the same time. You can also interpolate numerical integrals. The problem with my function is ...
64 views

### How can I kill one evaluator from another?

I have a kernel named A in one notebook and other notebook with kernel B, how can I kill B from A?
371 views

### Why does Hash return different values in Version 7?

This function does not work correctly for me. The generated Gravatars do not match the ones actually produced by using the corresponding address. The problem was traced to differing output from the ...
136 views

### Using bin values and metadata in ChartElementFunction in histograms

The DensityHistogram command lets you specify a ChartElementFunction which according to the documentation: The arguments ...
429 views

### Gravatars/identicons with Mathematica

The default avatar/identicon is based on an MD5 hash of your e-mail address. With some e-mail providers (e.g., GMail) the address gmailuser+foo@gmail.com is still ...
514 views

### Evaluate while external command is being run [duplicate]

Possible Duplicate: Computing Many Slow I/O Operations I'm launching an external command with the Mathematica front end that takes two arguments: ...
665 views

### Ordering vertices with minimum Edge Crossing in Circular Graphs

Weighted and sorted Mathematica circular graphs are shown below. My question is how to reorder the vertices in such a way that they have minimum cuts (intersection of edges) while keeping the circular ...
2k views

### Plot Even Piecewise function

Is it possible in Mathematica to plot an even piecewise function like: $f(x) = \begin{cases} 3t , 0 \le t \le \frac{\pi}{2} \\ 3t + 6 , \frac{\pi}{2} \le t \le \pi \end{cases}$ which has ...
173 views

### How to distribute a generic function of two arguments (without evaluating the arguments)

I guess there is an easy way to do this, but I can't seem to figure it out. What I would like to do is to distribute a generic (i.e. without specifying what this function really does) binary function. ...
718 views

### How can I create a legend for a Heat Map when I don't want to show the full range of colors?

I produce a heat map with legend with the code shown below ...
790 views

### Implementation of Balaban's Line intersection algorithm in Mathematica

I'm trying to implement a Brillouin Zone algorithm within Mathematica, including the generation of Brillouin zones of higher order in 2D and 3D. There is a nice implementation of generating these ...
607 views

### Compiling a recursive formula

My question is related to computing what is called "invariant measure" for a particular well known fractal - the Sierpinski triangle. We have an array m of four two by two matrices, say ...
84 views

### Exporting CellFrameLabels to HTML

I have a notebook that has several cells with CellFrameLabels and I'd like to export the notebook to HTML. However, the CellFrameLabels are lost during export. Here's an example of what I'm working ...