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
52 views

Is it possible to use FormObjects and FormFunction in a stand-alone notebook?

I have been looking at the FormObject and FormFunction. Can FormObject and ...
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1answer
131 views

Fibonacci Line Search Method

I am attempting to write a code to find to bracket the minimum of a function using the Fibonacci Line Search Method, I believe my code is well written but I am not ...
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2answers
79 views

Subroutine execution repetition

I like to write second and third lines repeated operation only once as a separate module with some Name. In each main program line a set of different set boundary conditions data is given,Name invoked ...
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1answer
157 views

For loops in Mathematica [duplicate]

I'm actually the first time using loops in Mathematica. For example, I have: For[i = 1, i <= n, i++, For[j = 1, j <= n, j++, ....] How it is possible now ...
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2answers
212 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 $n=2$: ...
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1answer
925 views

Euler's method for system of differential equation

I need to program Euler's method to solve a system of two diffferential equations of first order. Fist, I have programmed the Euler's method for just one differential equation: ...
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2answers
154 views

How to automatically put the part of a variable name after the first letter in symbolized subscripts?

So here is what I have thought: Use ToString and StringLength in order to get the number of characters in the variable name. If it is bigger than one, change variable name by putting everything but ...
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1answer
100 views
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1answer
267 views

Pseudo-code for rules of probability?

I am having a hard time in Stats understanding some basic rules of probability and set-theory, namely $P(A|B)$, $P(A\ \textrm{and}\ B)$ and $P(A\ \textrm{or}\ B)$ where $A$ and $B$ depend on each ...
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1answer
250 views

Handling Overflow

I have a notebook which takes in a user-defined function and starting value and tracks the orbit of the particle under iteration of the function. The problem occurs when the user enters a starting ...
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1answer
796 views

How to run Mathematica using Mac Terminal

My question is so trivial and I'm sure most people in here know exactly how to do this, however I still don't know how to run Mathematica in Mac terminal! I need to use all the cores of my computer ...
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1answer
242 views

Automating sequential import of data from web

I am trying to import data from multiple web pages hosted by a single online source. The data is posted by the source as one data set per web page for each week of the year. I would like to import the ...
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1answer
193 views

How do I insert a piece of code in Mathematica?

In Fortran, I can use include "file" to insert a piece of code. Is there a similar method in Mathematica?
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1answer
229 views

How do I slice an image of size “width × height” in n² pieces of size “width / n × height / n”?

Background: What I want is to make a jigsaw from an image. (A simple one where the pieces are polygons.) I have the following strategy in mind. Create a set of polygons and assign images (or just the ...
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58 views
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2answers
103 views

How do you apply an algorithm individually to an array with many graphs

I have and array with many graphs to which I want to apply an algorithm (below) to each graph in an array that contains all my graphs. ...
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2answers
359 views

Plotting an orbit using first principles [duplicate]

I am fairly new to Mathematica, but I am trying to plot an orbit of the Earth around the sun using the equation: $\quad r(t+dt) = (2 - G*M*dt^2/r^3)*r(t) - r(t-dt)$ I need to break this into ...
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1answer
218 views

Programming- cryptography

I have defined the following function in Mathematica to get a SET OF m SETS (these sets are the codes {p,q,d,e,n} for the ...
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2answers
288 views

Plotting in the “Manipulate” function - simple coding

Hello Mathematica community, my name is Preston! I have a real quick question that should be easy to answer. Alright, so for a research project that I'm involved it at my university, I need to ...
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1answer
209 views

Calculating mean of multiple stochastic processes and setting a lower threshold

Thanks to “Rod Lm” I got some very nice input for the following problem. My intention is to simulate within a Manipulate function a given number of possible stock ...
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1answer
110 views

How can I find the row differences of a matrix?

How can I compute the row differences of an m x n matrix to obtain an m-1 x n matrix; that is, given how do I obtain
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2answers
265 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 ...
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1answer
241 views

How can Time be made to go backwards?

I would like to make a countdown timer, but cannot find a reliable method to make the DateList[] function reverse. The not so robust code for the Digital Clock with the display of seconds follows: ...
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1answer
73 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 ...
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2answers
100 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: ...
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1answer
47 views

Implicit region is not “valid” in ParamatricNDSolveValue function?

I am trying to solve a geometric problem with relation to my Schrodinger equation and its boundaries. Here is my code: ...
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1answer
66 views

Ways to protect certain parts of expressions

I am currently working on a quantum mechanics problem where I try to find equations that relate different states of a many-body system. The states are described by sets of pairs of integers, like ...
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1answer
140 views

How would I obtain a list of column names in a Dataset?

I really love the addition of Dataset to Mathematica. I would like to write a basic utility function that exports a Dataset to Excel. Is there a way to get a list of column names from a Dataset?
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2answers
57 views

How to get the outermost command evaluated first?

I have an expression like ToString[Stuff[...]]. I plan on having the Stuff[...] be manipulated as a string according to the output of other parts of the program. The problem is that Mathematica tries ...
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2answers
98 views

Using conditionals to check if LinearSolve found a solution

Is there some way to check if LinearSolve found a solution using conditionals in Mathematica 9? I need to solve a large number of linear equations, but I am only interested in the cases where there ...
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2answers
67 views

Changing a tag when one function is passed into another using UpValues

I have two complicated functions f[x,y] and g[t]. Before the main evaluation code in ...
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1answer
62 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 ...
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2answers
110 views

Clearing arguments passed to a Module

Is there a possible way to clear the arguments passed to a module to release some memory. I believe that arguments passed to modules are passed by value rather than pass by reference. e.g. I have the ...
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1answer
150 views

Read expression from Mathematica via Mathlink C++

This is a simple C++ program to send an expression to the_Mathematica_ Kernel and get its response. ...
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1answer
67 views

MLEvaluate() Function Gives Error

I am trying to link my C++ program to Mathematica Kernel. I am trying to use the MLEvaluate() evaluate but I receive an error while compilation. My codes are as below: ...
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2answers
119 views

How to return matching sublists or empty list

How to return matching sublists or empty list m1 = {{1, 0.5}, {2, 0.4}, {3, 0.1}}; m2 = {{1, 0.5}, {0, 0.4}, {0, 0.1}}; Commonest[Join[m1, m2]] out: ...
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1answer
235 views

Making an animated simulation without procedural loops

I'm still new to Mathematica and this is the first time I've wanted to do something more complicated than plotting and changing parameters of mathematical functions. I want to make a simple ...
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1answer
151 views

How can I import sound from within a Manipulate expression?

I want to import sound from a file, record, and import sound. ...
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1answer
790 views

pointer like operations in mathematica and evaluation control

I would like to create a data structure of the type "header[pointer]" where pointer would point to a list. I will shown on an example how I'd like this to work, and where the problems are. ...
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2answers
238 views

Checking equality with ComplexInfinity and testing whether a function is (mathematically) undefined

This seems ridiculously basic, but I cannot find anywhere explaining how to do it. If you evaluate certain undefined functions like 1/0 or ...
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1answer
169 views

What is the new command for AffineMap?

AffineMap was present in Mathematica version 4. What is the equivalent command in the current version of Mathematica?
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1answer
111 views

Draw from HistogramDistribution with ParallelTable

I wanted to check something, but ran into troubles using HistogramDistribution in combination with ParallelTable. The code does the following: Compute a HistogramDistribution of some sample and use ...
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1answer
39 views

How to reference StringExpression named parts from a package without full Context path?

I have a long StringExpression in a package returned by a function. There are some named parts in the expression that I would like to reference when I use the ...
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1answer
74 views
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61 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 ...
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1answer
47 views

Why this isn't a valid argument? [duplicate]

I am having truble understanding why F1 produces an error, since both time and velocity are the same kind of object: ...
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1answer
52 views

Emulating Case Pattern replacement

As most regular users, I have developed utility functions complementing the Wolfram language for frequent tasks. In particular, I have variations on Cases (see ...
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1answer
105 views

Perceptron: Do loop not returning a value

I am trying to write a function that finds a simple best fit line for some data (Perceptron algorithm). Sadly it returns no output at all. Here's the code below: ...
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1answer
86 views

Hypothesis Testing and Formatting Output

I am trying to write a function that tests hypotheses and gives me a nice table but I can't. I need forum's help. For example, I have the following data ...
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1answer
231 views

How can I call the R-programming packages in my Mathematica?

I am trying to call the R-programming package called highfrequency in my Mathematica so that I can use its function rCov. I ...