3
votes
1answer
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 ...
6
votes
1answer
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 ...
7
votes
1answer
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.
11
votes
4answers
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. ...
2
votes
1answer
270 views

About high dimensional integrals

I want to be able to do high dimensional integrals like, (..naively I wrote it as this..) ...
5
votes
3answers
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 ...
4
votes
3answers
364 views

Generate a Combination of letters by a number

I'm trying to write a function f. example: ...
1
vote
0answers
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 (...
2
votes
1answer
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: ...
7
votes
1answer
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 ...
3
votes
1answer
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. ...
1
vote
2answers
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 ...
5
votes
2answers
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: ...
3
votes
1answer
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 ...
6
votes
1answer
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 ...
11
votes
1answer
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: ...
13
votes
6answers
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?
11
votes
1answer
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, ...
7
votes
1answer
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 ...
3
votes
3answers
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. ...
1
vote
2answers
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 ...
3
votes
0answers
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 ...
1
vote
2answers
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 ...
24
votes
1answer
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, ...
1
vote
1answer
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 ...
4
votes
2answers
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. ...
11
votes
1answer
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 ...
1
vote
1answer
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 ...
5
votes
3answers
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 ...
12
votes
4answers
1k views
13
votes
2answers
1k views

How do I add arrowheads to circular arcs?

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 ...
13
votes
1answer
632 views

Adding ContourLabels changes contour colors?

I have an array s5 I want to plot using ListContourPlot ...
3
votes
2answers
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: ...
3
votes
0answers
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 ...
0
votes
0answers
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 ...
2
votes
0answers
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 ...
4
votes
1answer
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?
9
votes
3answers
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 ...
3
votes
1answer
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 ...
15
votes
1answer
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 ...
6
votes
2answers
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: ...
6
votes
1answer
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 ...
3
votes
2answers
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 ...
4
votes
3answers
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. ...
3
votes
2answers
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 ...
14
votes
2answers
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 ...
9
votes
1answer
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 ...
1
vote
0answers
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 ...
7
votes
1answer
810 views

Implementation of Incomplete Fermi-Dirac Integral in Mathematica

I'm working on a special algorithm to implement a more accurate effective mass calculation for hole carriers in silicon in Mathematica. This rather involved algorithm uses incomplete Fermi-Dirac ...
4
votes
1answer
121 views

Pre and Post in a Block[]

Why does Block[{$Pre = ( 1 + #) &}, 1] produce 1 while ...

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