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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1answer
25 views

How to define a number of infix operators with predefined relative precedences

Reading a number of questions about infix operator notations I want to ask if somebody could reimplement the problem below in a simpler way, say modifying ...
1
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2answers
100 views

intermediate steps of a Mathematica operation

How to make a multiplication or division, the intermediate steps. The numbers can be rational - decimals? it seems the OP merely wants Mathematica to show him how to multiply and divide the way ...
1
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1answer
60 views

Program to demonstrate rotation according to quaternion values

On the Wolfram|Alpha website, I type quaternion(1,1,1,1) into the search field. Wolfram|Alpha shows a 3D transformation of the quaternion values representing the orientation of an object. I have 9 ...
0
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1answer
347 views

Mathematica Implementation of Householder’s Method

I typed the Householder code in this paper, which starts on page 7. The code is: ...
5
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1answer
599 views

How to implement Kemeny-Young method? (rank aggregation problem)

Prehistory I am trying to make some statistical analysis of some experimental data, arises from measurements made ​​on an ordinal scale. I faced with the problem of rank aggregation: to get from ...
0
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0answers
51 views

Mathematica requirements management [on hold]

Is there a way to use Mathematica notebook as a requirements document as it's possible in IBM DOORS ? ...
2
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1answer
65 views

Clean & efficient bounding box non-intersection test

I would like a quick test to tell me that segments $ab$ and $cd$ cannot intersect in the plane. If the maximum $x$-coordinate of $a$ and $b$ is less than the minimum $x$-coordinate of $c$ and $d$, ...
8
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3answers
363 views

Calculating integral by Romberg Algorithm

In my "Numeric Anasyis" course, I learned the Romberg Alogrithm to calculate the numerical integral. The Romberg Alogrithm as shown below: $$ ...
3
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2answers
72 views

How to define UpValues about the derivative of NBSpline when the length of knots is unknown?

Description In the book “Programming in Mathematica” 3rd by Roman.E.Maeder, the author gives a topic about A new Mathematical Function in section 8.4. For instance, for the following formula: ...
5
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1answer
92 views

Efficient upsampling of multidimensional array

I would like to efficiently upsample a multidimensional array. It's a 5000*5 matrix where each element is a submatrix 12*12 and it is that 12*12 matrix I want upsampled (to 24*24). The upsampling ...
12
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9answers
486 views

Generating a matrix using sublists A and B n times

I want to write a function that generates a square matrix from sublists. My sublists are a = Range[0, x, 0.5]; b = Range[0.25, x + 0.25, 0.5]; Suppose x=2, then I ...
1
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2answers
95 views

How to write a loop

I try to create a table which will describe traffic paths at a crossroads. Instead of using copy-paste repeatedly, I would like to write a loop. For example: ...
2
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0answers
62 views

What am I missing in this highly oscillatory integral?

I want to numerically integrate this equation (in python without calling Mathematica): $\int_0^\infty {\rm d}k f(k) J_v(r k) J_n(s k)$ where $f(k)$ is a non-smooth function, $J_v$ are the Bessel ...
7
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2answers
212 views

How to define the Bernstein function like the built-in BernsteinBasis?

We know the Bernstein function defined as below: $$B_{n,i}(u)=\binom n i u^i(1-u)^{n-i}$$ And we define $B_{n,i}(u)=0$ when $i<0 $ or $i>n$ In addition, the first derivative of $B_{n,i}(u)$ ...
360
votes
13answers
77k views

Where can I find examples of good Mathematica programming practice?

I consider myself a pretty good Mathematica programmer, but I'm always looking out for ways to either improve my way of doing things in Mathematica, or to see if there's something nifty that I haven't ...
4
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1answer
53 views

How to add UpValues to a symbol to make a expression expanded normally?

Here is a implementaion of Bernstein basis function. I add the following UpValues to ...
4
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1answer
293 views

Maximizing functions with Which statements

I'd like to be able to find the maximum value that my Capex function (see below) generates. This is a fairly simple function so I could just add it up but I have more complex functions of a similar ...
10
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2answers
235 views

Checking the argument of user-defined function with side-effect method

Today, I answered a question of mine that asked two month ago. Please see here Now I would like to add the argument checking in this function. Then I used a method that Mr.Wizard answered ...
4
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2answers
318 views

A bug fix to mathematica 10.0.1.0

There is a bug in the Wolfram Symbolic Transfer Protocol Development in C (Windows). I described it in the next answer by myself, from which I summarize: One cannot successfully compile the ...
128
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1answer
23k views

Mathematica Minecraft

Some time ago I asked myself: with all these great graphics and interactive capabilities of Mathematica, what kinds of 3D games can be implemented in it? And the answer which came to mind is ...
2
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2answers
196 views

Issue with Set function

Tables often come with column headers. Indexing the columns with the header is a natural thing to do. Although a proper dictionary is the usual solution in such a case, I find it often practical and ...
-2
votes
1answer
155 views

How to get the coordinates of points within an image?

How can I get the coordinates of an image, and make Mathematica draw the image from the coordinates found? I am interested in just the outlines of the regions. Here is an example of the kinds of ...
3
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1answer
96 views

A pre-parsed HoldForm

HoldForm holds an expression's parsed form not its actual "inputted form" e.g. ...
1
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1answer
117 views

Multiply out product of sums

For a specific quantum mechanical problem I need to multiply out operators in order to calculate a trace by hand. For example I need a Hamiltonian squared with $H^2$. The Hamiltonian contains of a few ...
5
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2answers
202 views

How do I “evaluate in place” programmatically? Need to evaluate Defer[] result in non-interactive setting

I need to evaluate the result returned from an external package, which contains Defer in it, but do this in a script without user interaction. I am not able to ...
259
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25answers
34k views

What are the most common pitfalls awaiting new users?

As you may already know, Mathematica is a wonderful piece of software. However, it has a few characteristics that tend to confuse new (and sometimes not-so-new) users. That can be clearly seen from ...
12
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1answer
208 views

How to add AccuracyGoal and PrecisionGoal options in a numerical function?

There are many built-in functions that contain AccuracyGoal, PrecisionGoal and ...
3
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1answer
129 views

How can you get the area of a region from an image?

Suppose we have a square of side "L" m, How can I calculate the hatched area, if the corners of the square are centers of circles. It can be generalized to any region? edit: This is the result I ...
7
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2answers
349 views

Association and rudimentary object-oriented programming

Doesn't Association provide us rudimentary object oriented programming via constructs like ...
2
votes
1answer
181 views

How can I invoke the solution of NDSolve to determine a parameter in my equation just inside NDSlove?

I am trying to solve a differential equation by NDSlove for $h(x,t)$. It reads $$h_t=h_{xx}-V_h-\lambda(t)$$ where $V_h$ is a given function of $h(x,t)$ denoted by ...
12
votes
4answers
606 views

How to implement dual numbers in Mathematica?

I wonder how can I implement dual numbers in Mathematica, so that all functions work well with them (as with complex numbers). Particularly, for each function $f$, ...
7
votes
1answer
101 views

How to select a submatrix containing similar elements from a matrix? [closed]

( This question is related but does not ( fully ) answer my questions. - Finding the position of similar elements in a matrix ) I have not written code yet, I am in the design phase of code for the ...
6
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1answer
68 views

Can Query operators be naturally cast as either Ascending or Descending?

One of the challenges of coming to grips with Query's on Association's and Datasets is ...
0
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0answers
38 views

Programming of basin of attraction for with memory iterative methods

I have made the programming for without memory method and i got the basin of attraction but i could not make it for with memory iterative method. I am sending you the programming of with memory ...
3
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3answers
517 views

Need help with exception handling

I have read the docs for Catch, Throw, and friends multiple times, and I confess that I find them utterly incomprehensible... ...
4
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1answer
131 views

How to check the option value?

Given that I have a function func as follow: To check the value of options, I using the step-by-step method If[] ...
54
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2answers
2k views

What are the best practices / most common / idiomatic ways to report errors in Mathematica?

In particular, what are the best ways to report errors about incorrect arguments to a function? Checking for the correct arguments is relatively easy using patterns, but how to report an informative ...
2
votes
1answer
83 views

Implicit derivatives in one line. How do I do it?

I have this little script to derive implicitly $PrePrint = # /. {D[y_, x_, NonConstants -> {y_}] :> y'[x]} &; Example: ...
0
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1answer
48 views

Write a function pollard[n, B] that tries to factor an integer n, using Pollard's p − 1 method with at most B iterations [closed]

This is what I got but it seems it's not working. When I test it, it just goes through and nothing gets returned. Is there something I'm missing? ...
6
votes
1answer
118 views

Is there a practical way to define a default value for missing keys in an Association?

It can be very useful to define background or default value for an object that can be incremented or otherwise modified. A simple (and for me, common) use is a counter: ...
3
votes
1answer
130 views

Programming for matrix manipulation

I want to write a programme which operates on nd x nd matrices. The programme looks the matrix as a n x n block matrix where ...
3
votes
1answer
100 views

Using function to transform a list

I have a list like that: {{Integer,String},....}, integer ranges from 1 to 900 and String "I" to "IV". And I need to find which pair of {x,y} each sublist is related to, so i can get a new list like ...
1
vote
2answers
83 views

Ask about the variable and constants in partial derivative in a loop

EDITED I have a function in a list like : func={2(x^2)+x*y+3(y^2)}; I want to have a UI that ask me which parameter (x or y) is a variable in a ...
2
votes
2answers
64 views

Sum broken into two sub-sums according to a condition on the terms

I have a sum in mind, but I want to break it into two sums and get a separate total for each of the two. All cases where the square root is accurate, i.e., exact All cases where the square root is ...
4
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3answers
130 views

How to get multiplication of the elements of a specific list/Matrix

Assume there is a list: List1={a,b,c,d}; Then I want to get these calculation: ...
4
votes
1answer
65 views

How to define an expression which is differently evaluated in calculations and printed

Let's say, we have a list: values = {1.2, 0.04, 0.9}; Is it possible to replace 0.04 by some expression, which displays as ...
9
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1answer
104 views

How to implement a custom random process object?

I want to implement a custom random process thing1 to pass to RandomFunction. The process I have in mind is conceptually extremely simple: two alternating Poisson ...
0
votes
0answers
64 views

How to spend any image in “2D” or “3D” to an image mesh, ie as a wire frame in black and white?

How to spend any image in "2D" or "3D" to an image mesh, ie as a wire frame in black and white? For example some of these: edit :example output