Questions tagged [broken-code]
Use this tag only if you did your research and you still don't know why your syntactically correct code does not work.
108
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What's wrong with this FFT-based Von Kármán vortex street simulation?
About 9 years ago, I came across this interesting website, and found the following paragraph with a broken Mathematica code sample:
When fluid passes an object, it can leave a trail of vortices ...
- 63.4k
10
votes
2
answers
5k
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How to set up a simple Monte Carlo simulation?
there is a 1% chance that there will be a scattering event, if there is a scattering event the direction of scattering will be determined by a random sample of the custom[a_] function and if there is ...
- 153
10
votes
2
answers
1k
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What is the Difference Between Rule (->) and RuleDelayed (:>)?
I am new to Mathematica so this question may seem rudimentary. Sorry for that! :)
I want to implement the well-known property of Kronecker's Delta
$$\Sigma_{i=1}^{n} a_i \delta_{ij}=a_j,\quad 1 \le ...
- 1,707
7
votes
2
answers
514
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Sound synthesizer using Manipulate
Sound synthesizers, both digital and analog, often include a parameter section for shaping the amplitude of a sound wave over time. This parameter section is commonly known as an "ADSR EG" (attack, ...
- 415
7
votes
1
answer
425
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What is wrong with this code? (Usage of FunctionInterpolation and how to make code efficient)
I am trying to create an interpolation out of a function that comes from an improper integral. The end goal is to make a 3d plot over a specific region. Specifically, I have the following code:
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- 561
6
votes
2
answers
171
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A box structure with a depth exceeding the maximum allowed depth was encountered
I am trying to perform the task in Mark McClure's article Parametric L-Systems and borderline fractals. I have copied his opening code on the first three pages:
...
- 14.8k
6
votes
2
answers
174
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NonlinearModelFit inside Manipulate
I can't understand why this behavior with my code... I'm trying to visually adjust the best parameters to fit my model, everything is working fine, less the part of adjusting the model.
...
user48983
5
votes
1
answer
133
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5
votes
1
answer
562
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Label State Space Models converting ODEs
Say I have a set of differential equations not necessarily in first order form. I would like to build the corresponding state space model. When equations are many and long, it becomes difficult to ...
- 2,150
4
votes
2
answers
515
views
4
votes
4
answers
271
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Efficient generation of n-bit base-m Gray code with adjacent bit changes
How can I generate n-bit base-m Gray code in Mathematica, where only 1 bit changes at a time and all possibilities are covered? I have been hitting my head against a metaphorical wall for a few hours ...
- 53
4
votes
1
answer
366
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Why Min cannot be used as constrains of NMinimize?
I met a strange problem when trying to do an optimization.
Initialization code,
...
- 1,429
4
votes
2
answers
164
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Adding numbers with defined precision produces incorrect result
I've tracked a bug in my code down to the problem of adding two numbers together, with the left argument having machine precision, e.g by 3` . The issue is, if ...
- 557
4
votes
1
answer
894
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Issue in ParallelTable after evaluating another function using NDSolve and FindRoot. What is wrong with this inverse?
I am trying to find the inverse of a function which is defined through NDSolve and NIntegrate.
The question is pretty similar ...
- 1,201
4
votes
1
answer
123
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How to get rid of 0.000 and change 5.*10^n to 3*10^n on Log Plots?
Using Version 13.1.0.0 (Edit: MacOS BigSur Version 11.6, Hardware M1 chip)
In order to show some Log (or LogLog) plot features that I find annoying, here is some code:
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- 695
3
votes
2
answers
2k
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3
votes
3
answers
1k
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For-loop not working as I expect
I want to do this:
When 10 <= t < 130, give t -> 1;
When 130 <= t<300, give <...
3
votes
2
answers
640
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Solving a reaction diffusion dystem [closed]
I have a problem solving a numerical reaction diffusion equation. It emits the following message:
RecursionLimit::reclim2: "Recursion depth of 1024 exceeded during evaluation
How can I solve this ...
- 31
3
votes
2
answers
166
views
3
votes
1
answer
137
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some confusion about ReplaceRepeated
This is Right.
NestWhile[Log, 100, # > 1 &]
{100} //. {x_} /; x > 1 :> {Log[x]}
100. //. x_ /; x > 1 :> Log[x]
This is wrong,why?
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- 3,653
3
votes
2
answers
120
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Why does introducing value of variable for NDSolve via function not work for this problem?
I am very confused and even restarted Kernel several times (Mathematica 13.1 Windows 10). However, I fail to understand why one evaluation of NDSolve works while a ...
- 8,900
3
votes
2
answers
291
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Extract mesh coordinates from a LaplaceSolution Plot
I have made a code for the solution to a particular problem involving the Laplacian, and after plotting in 3D the resultant potential, I have tried to look for a ...
- 85
3
votes
1
answer
115
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3
votes
1
answer
376
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Optimization of power tower fractal generator [closed]
I tried to optimize the code for generating power tower fractals from here. As the author suggested, I tried to memorize the points already tested in a list.
Here is my code :
...
- 55
3
votes
2
answers
744
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EdgeRenderingFunction question
Bug introduced in 9.0 and fixed in 10.0.0
(Edit 1 : I added this paragraph after the original post, for context)
Some context for this question can be found in another post (https://mathematica....
- 475
2
votes
5
answers
2k
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Where did I go wrong with my implementation of finding a plane tangent to a surface?
I am working on finding the plane tangent to a paraboloid at a given point.
My code:
...
- 595
2
votes
1
answer
222
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Stability classification code for dynamic system
I'm interested in carrying out stability analysis on discrete dynamic systems, as was done in this paper. The Author used their function ...
- 522
2
votes
1
answer
367
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Getting errors when I try to evaluate code taken from Trott's Mathematica Guidebook for Graphics
I would like to learn how to make high quality images in Mathematica. In my pursuit, I have come across Michael Trott's Mathematica Guidebook for Graphics. I have been trying some of the examples, ...
- 21
2
votes
2
answers
515
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Weighted mean of complex exponential function using NIntegrate
I have defined the following functions:
...
- 259
2
votes
1
answer
176
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Python Code to Mathematica for Classical Map of Kicked Top
I am trying to convert this Python code for Classical map of kicked top to Mathematica.
For a single trajectory, I am able to ...
- 1,524
2
votes
1
answer
166
views
How to combine Graphics primitives in a DynamicModule without breaking it
I am trying to present Graphics primitives dynamically. I want the displayed image to be able to update after the user changes the controls. An example would be ...
- 4,185
2
votes
1
answer
51
views
User Implemented SHA-1 is failing for strings of length >512 bits
So, earlier, I posed a question regarding getting a user implemented SHA-1 hash function to work correctly. Well, I fixed the problems, cleaned it up a little bit, but now I have the problem for when ...
- 445
2
votes
1
answer
162
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Code for finding multiple roots only finding two
I've an issue with my code. I am basically trying to get the n-th root of a function. My code finds two roots correctly, but for others, which I think should be distinct, I get the two roots repeated ...
- 121
2
votes
1
answer
265
views
Why different output is obtained for the same code (Mathematica 10.1)?
I wrote some code in Mathematica:
...
- 2,570
2
votes
1
answer
126
views
Python to Mathematica code bug
I have an assignment in Mathematica, which I've already solved using Python and it's a bit hard to convert the code. Here's what I have done so far:
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- 133
2
votes
1
answer
121
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How to partition $[0,1]$ into $m$ equal sub-intervals and count the number of sub-intervals that intersect with my cantor set?
Suppose I define my cantor set as
...
- 39
2
votes
0
answers
46
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ParallelTry Hangs on previously working code
When I run the below ParallelTry command, it just sits on it and says its being evaluated, but I cant abort it, it doesn't return what I am expecting, and I have to ...
- 557
2
votes
0
answers
43
views
How can I fix this cycle in order to iterate several times? [closed]
I have been working on a code whose only purpose is to get the mean value over four numbers. And I managed to do one cycle, however after trying to repeat this process until a certain condition is ...
- 85
2
votes
1
answer
1k
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NDSolve: Indeterminate expression 0. ComplexInfinity encountered? [closed]
The following code give errors that I don't understand.
Could you please suggest a method to solve these differential equations?
...
- 65
1
vote
2
answers
432
views
What's wrong when I use NestWhileList?
Problem :
A Happy number is a number that if one squares its digits and add them together, and then take the result and square its digits and add them together again and keep doing this process, ...
- 595
1
vote
3
answers
540
views
Solving cubic equation with unknown coefficients
I am trying to solve a cubic equation with unknown coefficients (p and t), here is the code:
...
- 1,472
1
vote
3
answers
77
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Labeling point coordinates in path graph using VertexLabels
Question: How do we label point coordinates in Pathgraph using VertexLabels.
Suppose we have a list of points ...
- 39
1
vote
2
answers
824
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Michaelis–Menten kinetics using Gillespie Algorithm
I am trying to implement Michaelis–Menten kinetics using Gillespie Algorithm.
$$\text{Reaction 1:}\quad E+S\rightarrow C$$
$$\text{Reaction 2:}\quad C\rightarrow E+S$$
$$\text{Reaction 1:}\quad C\...
- 10.5k
1
vote
1
answer
879
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Error message: Coordinate index 0 is out of range for the enclosing GraphicsComplex
I am unable understand following error message: Coordinate index 0 is out of range for the enclosing GraphicsComplex. How to fix it?
Attached data here: pts and polygons. See also end of question.
<...
- 427
1
vote
3
answers
267
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Creating an interactive plot that zooms into the function
Suppose we want an interactive plot for the code:
...
- 39
1
vote
2
answers
233
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QR decomposition using Gram Schmidt [closed]
First of all I don't want to use the reflection method, only Gram-Schmidt.
So here's the program for Gram-Schmidt:
...
- 11
1
vote
1
answer
99
views
Please help me find my error [closed]
When I use variables, errors are encountered. But when I change the variables to constants, I don't have a problem, but I wonder why.
...
- 31
1
vote
1
answer
108
views
1
vote
1
answer
103
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Outputting probability of rolling 6 dice N times, generating a new output each roll
I am looking to output the probability of n classic six-sided dice but I am not sure how to go about starting. This is what I have written out so far, but no way to go about accounting for n dice for ...
1
vote
1
answer
71
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Help Calculating My "Deviation"
I created a "distribution deviation" where for $\left\{a_1,...,a_k\right\}$ we take all take the mean of all combinations of $\frac{\min\left\{a_{i},a_{j}\right\}}{\max\left\{a_{i},a_j\right\...
- 39