Questions on writing non-trivial programs in Mathematica. Do not use this tag for questions on plotting/graphics or for questions on doing mathematics with Mathematica, where the focus is more on the math than the program.

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1
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1answer
93 views

How determine The most possibility probable with programming

i have a scatter chart of probable of happen some thing like below chart link of google chart i what determine the probable The most point in below chart , can use a mathematic method to determine ...
5
votes
3answers
140 views

Prevent iterator name from being confused with symbol passed into function body

I have a massive amount of code with lots of Table and Sum inside a Module. Each with their ...
8
votes
0answers
119 views

Can code optimize code?

Are there functions, programs or packages that deal with optimizing mathematica code i.e. re-writing ineffecive or convoluted code. -This question has haunted me since I joined SE. The background for ...
7
votes
1answer
164 views

How can I only draw outer common tangent to two circles?

I have code worked for drawing common tangent lines to two circles(http://en.wikipedia.org/wiki/Tangent_lines_to_circles), now I want to delete the inner common tangent lines, how? ...
1
vote
0answers
132 views

What are the best tips in Michael Trott's beer/whiskey Wolfram Blog post? [closed]

Michael Trott posted this incredible tour-de-force on the wolfram blog: http://blog.wolfram.com/2014/08/19/which-is-closer-local-beer-or-local-whiskey/ The length of the post is overwhelming, so I'm ...
10
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2answers
205 views

Why isn't Lookup treated like other symbols?

With Mathematica 10, I wanted to overload Lookup using TagSetDelayed, but it doesn't work. For instance, if I define two objects ...
3
votes
2answers
67 views

How to define a nestable Baseform function, BaseForm output becomes BaseForm input

Mathematica won't change a number's BaseForm recursively: 63969 // BaseForm[#, 16] & // BaseForm[#, 8] & // BaseForm[#, 2] & Well, I inspected former ...
16
votes
6answers
713 views

How to understand the usage of Inner and Outer figuratively?

Description: In Mathematica the functions like Thread, Inner, Outer etc. are very important ...
5
votes
1answer
175 views

How can I make a “self-referential” replacement operation self-contained?

Fairly often I find use for replacement rules that call themselves on the right-hand side of the rule, e.g.: ...
0
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3answers
140 views

Avoid creation of OwnValues when inserting transformation rules into Experimental`OptimizeExpression

I have a large list of transformation rules that I want to simplify. I find Experimental`OptimizeExpression works as it gets me the answers. My question is: **I can only get this to work when I ...
30
votes
0answers
325 views

Is this 30% slowdown in Mathematica 10 due to DownValues lookup time?

Running several numerical self-programmed packages I realized already some time ago that Mathematica 10 needed between 20 and 40% more time. I did already report this of course with a simple example ...
4
votes
3answers
193 views

Skipping over iterator values in a Table

I have been using the built-in function Table for some computations. (The following is not an actual representation of the equations I am using). ...
3
votes
2answers
147 views

The value of an option inside a native function

I'm looking for something similar to AbsoluteOptions but that can be evaluated inside the function. That is, I want to read the absolute settings of options ...
2
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0answers
40 views

Maximizing Large Multivariable Function over Region with Parameter Constraints

Brand new Mathematica user here. I have a complicated function to maximize, and thought I would try software like Mathematica instead of taking derivatives by hand. I found some Mathematica ...
4
votes
0answers
54 views

How to save the result in the Notebook (.nb) and shut down the computer when the calculation is done

I have a notebook(.nb) which its calculation is time-consuming and long. I can not observe it if the calculation is done or not. Therefore, I want to : (1) Save the results in the notebook(.nb) ( I ...
0
votes
1answer
58 views

Problem with Maximize

As $\{p1,p2,p3,p4,p5\}$ represents a probability distribution and $l1,l2$ are the eigenvalues of a stochastic matrix, the function $f$, as defined below, has to be maximized over a certain region. ...
-2
votes
4answers
165 views

Compare elements in a list

Assume that there are three different points in x-y coordinate like: p1={4, -1}; p2={5, -2}; p3={1, 5}; In order to compare these points to each other in a ...
2
votes
1answer
51 views

CreateDocument options needed to suppress the default notebook menu

What are the options needed in Mathematica 10 to suppress the menu on top of any notebook created with CreateDocument? For example, the Messages window as well as the windows generated by ...
0
votes
1answer
93 views

Need help in understanding code [closed]

I am just beginning with Mathematica. I have received this code to study. I am not able to follow this particular section. I have tried looking it up on many forums, with no answer. Can you help? ...
2
votes
1answer
152 views

Converting a nested for loop from MATLAB

In MATLAB I have the following series of nested for loops that update a matrix. (It's not my code, but someone else's that I'm trying to replicate - I don't know ...
0
votes
1answer
55 views

Is it possible to build/simulate/extract data from a System Modeler model completely inside a notebook using the MathModelica language syntax?

See examples in: http://www.mathematica-journal.com/issue/v10i1/contents/MathModelicaPaper/MathModelicaPaper_2.html It seems to be ruled out by the statement (Chapter 2 intro): "The subset of the ...
4
votes
2answers
73 views

Why can't I pass in a product of matrices in my modified matrixform? [duplicate]

In attempt to build a function that would work like MatrixForm but would wrap a matrix with brackets, I tried the following function: ...
5
votes
5answers
460 views

Populate an upper triangular matrix from a vector of elements

What is the best way to populate an upper triangular (or alternatively: lower triangular or symmetric) matrix from a vector of elements? This example input: ...
0
votes
1answer
46 views

Help with programming(using list) [closed]

I would like to make a program which gives me what is the greater natural number "n" less than an arbitrary given natural number "k" which satisfy: for each prime divisor "p" of n, p^2-1 divides n. I ...
4
votes
1answer
132 views

Construct a function that can generate a geometry by extruding a section

Toady I want to construct a geometry shown as below: I know the Mathematica has the functions like Cylinder, Sphere and so ...
2
votes
1answer
74 views

How to program a clickPanel for chemical elements (like a periodic table)?

The command ColorData["Atoms", "Panel"] indicates RGBColors of "Atoms" by clicking a panel. As I don't want to reinvent the wheel, I asked myself: How to ...
0
votes
0answers
53 views

deleteduplicates Delete elements of a list [duplicate]

I have a math problem about Mathematica, I am looking help from you. I hope that you could help me. The Math Problem: list= { {0,0,1},{1,0,0},{0,1,0} ,{1,2,3}}; ...
7
votes
4answers
303 views

Computing the average over the values of the boxes surrounding a box in a grid

Recenty,I encounter a problem described as below: I have a table that owns many boxes,and each box has a sequence like 1,2,3,4,etc.In addition,every box has a value. Now I want to make the ...
9
votes
3answers
117 views

Implement settable properties

I am looking for advice on implementing the following. (It is possible that the answer is that it is simply not a good idea to do this.) I would like to have an object similar to ...
1
vote
0answers
41 views

Settings to disable global scope

I am building a fairly large application in Mathematica, and globally scoped variables are causing issues. I would like globally scoped variables to be out-of-scope for my expressions, except by ...
2
votes
1answer
142 views

How can I rewrite my code to make it simpler?

Two months ago,I written a function IRobot to caculate the $I_{xx},I_{yy},I_{zz}$ and $I_{xy},I_{xz},I_{yz}$,shown as below: ...
0
votes
3answers
128 views

How can I use NestWhileList instead of While in this case?

OK, the problem occurred when I challenged with Project Euler No. 10 The sum of the primes below 10 is 2 + 3 + 5 + 7 = 17. Find the sum of all the primes below two million. My code is: ...
7
votes
2answers
205 views

Using least independent rectangle area to separate every point

Description I want to add vertical line and horizonal lines between data to make every point have an independent rectangle area. In addtion, every independent rectangle has a number ...
3
votes
1answer
67 views

EndOfFile error

I have a LARGE file (14.6 GB) that I want to separate into several smaller files. Because of its size, using Import/Export is not feasible, I think the most reasonable way of handling this would be ...
1
vote
4answers
106 views

multiple sequential definitions, defining own set function

I want to define a function for doing multiple definitions, where I apply the same function f to all values, and definitions are done not at the same time but after ...
3
votes
2answers
140 views

Plotting: DensityPlot produces artifacts

I am trying to plot the electric potentials of bouncing balls using the following code: ...
0
votes
2answers
86 views

How to localize the symbols x,y, A, B in the following program? [closed]

I see a example in Paul Wellin's Programming with Mathematica An Introduction, 4th edition: ...
6
votes
1answer
265 views

What is wrong about Abs[x]-a? Is it a bug?

Why is the Out[74] not {1 - a, {x -> -1}}? ...
0
votes
0answers
66 views

Timing Differences

In More efficient implementation for comparing coefficient lists in a Do-loop link, george2079 posts in his first answer a piece of code that takes 352 seconds to compute. When I run this same piece ...
1
vote
1answer
52 views

Elements of a List according position in axis

({{a, b}, {c, d}}) a, b, c and d are Lists of 300 length. Their first 4 elements must specify their position in the column (1 column, 2 column, etc) and the ...
0
votes
1answer
126 views

How to represent the lines that are formed by the intersection of two planes?

I am trying to set up Brillouin zone and representing the lines that are formed by the intersection of two planes is part of my step. I have tried the sample sections from the graphics guide book, but ...
0
votes
1answer
141 views

For-loop only executes first line in body [closed]

I have a simple For[] loop: ...
1
vote
2answers
179 views

More efficient implementation for comparing coefficient lists in a Do-loop

I'm wondering how to speed up the following code so it actually computes for $n=2$: ...
0
votes
1answer
209 views

Obtaining the envelope of an oscillating function and perform fitting

There is an elegant way to obtain the envelope of an oscillation function explained here http://mathematica.stackexchange.com/a/27854/15966 My question is how to modify the code below so I can fit ...
0
votes
0answers
38 views

Automatic Cuda/CPU code; Fast programme run [duplicate]

I have developed my thesis codes by means of Mathematica software in a .nb file format. Despite using the available Parallel code capabilities and doing all the numerical integrations by means of ...
1
vote
4answers
131 views

Plot roots of B(z) according to angle small to large

I have the following function: B[z_]=((z*(z - 0.5)*(z + 0.5))/((1 - 0.5*z)*(1+0.5*z))) I want to plot the roots this polynomial according to angel like below ...
1
vote
0answers
79 views

How to construct a coordinate system that owns detailed calibration in the 3D enviroment?

Recently,I write a program to demonstrate the forward kinematics of the SCARA robot.The code showed as below: Using this function to construct the BigArm and ...
0
votes
2answers
50 views

How to output (anything) if any error happens

I have long code which goes through iteration process. some times I get error messages. I want to get the iteration numbers (or any kind of output indications) when errors happen. for example, how ...
0
votes
1answer
121 views

Differences between 'Solve' and 'LinearSolve' [closed]

Using the function 'Solve' I can do the following: Solve[a x + y == 7 && b x - y == 1, {x, y}] I get the following output: I want to get the same output using 'LinearSolve' instead. How ...
5
votes
1answer
181 views

Higher RAM handling by 32bit Mathematica [closed]

Can 32 bit Mathematica run program which requires more than 4GB RAM ?