Questions tagged [error-tracking]
The error-tracking tag has no usage guidance.
65
questions
1
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0answers
86 views
Why is Mathematica saying this sequence tends to $0$?
I am a complete novice in Mathematica so please bear with me. I am trying to graph a sequence that converges to $\pi$ but after $27$ iterations Mathematica just goes crazy and I am not sure why. I got ...
0
votes
1answer
58 views
Error test failure for the following system
My question is about a reason of the inability of Mathematica to integrate the given system of differential equations, that depends on parameters, in a stable way: for some values of the parameters ...
0
votes
0answers
61 views
Mathematica stops working with no warning/error
I have some long computations on my Mathematica notebook.
For some reason they stop and Mathematica gives me no reason as to why. No warning. No erros.
If run the "Initialization Lines" (...
1
vote
0answers
45 views
RegionPlot outputs System`ReduceDump`
I'm using Solve[] to find the solutions to a system of equations, then checking their stability in a Hessian using ...
1
vote
1answer
81 views
Strange error not found in a monte carlo code, Infinite expression 1/0 encountered
I've been trying to code a kinetic monte carlo simulation for a dimerization reaction, 2M ---> D. However I have a kinetic Monte Carlo code for a first order decomposition reaction of AIBN (that's ...
2
votes
1answer
83 views
How to implement an “if an error occurs”-condition in Mathematica programming?
In general Mathematica may return a value even if NDSolve has run into error.
A simple example is
...
1
vote
1answer
53 views
Why does the mix of Exclusions and SymbolicProcessing->0 sets my integral to $0$?
I am trying to compute a $5$-dimensional integral, which may or may not be zero. I do believe it is finite though, at least for the values $\epsilon$, $\sigma$ used here. The integral is given in the ...
5
votes
2answers
90 views
How to Quiet[] only the first argument of Check[]?
I have a Check of the form
Check[expr,failexpr, {NIntegrate::slwcon}]
If expr throws slwcon, I would like to redo the calculation with higher precision by ...
1
vote
1answer
54 views
Catching NDSolve Singularities
I am using NDSolve to solve a system of equations with changing initial conditions (I'm using NDSolve multiple times). However, for particular initial conditions I am getting an effective step size of ...
0
votes
2answers
53 views
NDSolve: How to perform a reverse integration consistency check?
Let there be the following NDSolve code:
s = NDSolve[{y'[x] == y[x] Cos[x + y[x]], y[0] == 1}, y, {x, 0, 30}]
I think it ...
2
votes
1answer
40 views
How can I properly use Catch[] to prevent my program from quitting?
I am getting an error depicting an Uncaught Throw, with the accompanying code being returned:
Hold[Throw[$Failed, CURLLink`Utilities`Exception]]
I have managed ...
1
vote
1answer
153 views
Why does Mathematica just return Hold of my Input? [closed]
Example:
Solve[x^2 + a x + 1 == 0, x]
Output: Hold[Solve[x^2 + a x + 1 == 0, x]]
What is the problem?
Any child can solve this in its head
2
votes
0answers
68 views
5
votes
1answer
159 views
Raise Warning/Error on invalid Matrix Addition and Multiplication
Consider the following code:
DiagonalMatrix[{1, 1, 1}] - 1
Mathematica interprets it in the way, that it substracts 1 from every matrix field while ...
1
vote
2answers
154 views
1
vote
0answers
61 views
raise error on type mismatch
Is there a best practice for raising an error on a type mismatch? For compiled functions I'm guessing the answer is the use of GeneralUtilities`WithMessageHandler. ...
5
votes
1answer
85 views
Ignore message in `Check` without silencing
Check[expr,failexpr,checkedMessages] will evaluate expr and if it encounters any of the messages in ...
0
votes
0answers
49 views
customisable error checking, message handling code
I have an iterated computation running in a while loop, which is bound to fail at some point, at which point I want it to stop, e.g.
...
1
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0answers
20 views
How to get a value from Error message? [duplicate]
I've looked pretty hard for a solution to this issue with no luck.
Hope you could give me a clue:
When I run NDSolve I get the following error msg:
...
1
vote
0answers
414 views
Kernel shutting down automatically with no error
What are the possible reasons why a kernel exits and the computation simply stops without printing out an error message?
In case the specific scenario is required, it is as follows but perhaps the ...
3
votes
1answer
121 views
Large residual error when solving a 2D BVP with NDSolve and Finite Element Method
I'm trying to solve a simple PDE (an inhomogeneous Helmholtz equation) in a disk domain with center at $(1,0)$ and radius 0.5 using the following commands
...
9
votes
2answers
3k views
Histogram with Error bars
I have a dataset for which Mathematica easily creates a Histogram. However I also need Mathematica to show error bars corresponding to 3 standard deviations for ...
1
vote
1answer
79 views
How to catch error messages from parallel kernels
Doing something that throws out an error (warning):
ParallelTable[NIntegrate[1/Sin[10 t], {t, 0, W}], {W, 0, 10, 1}]
In parallel somehow limits a possiblity to ...
3
votes
1answer
87 views
Saving a log file if an error occurs
I am running a program that adds a message to a list after each completed cycle (about 5k cycles). Upon completion, the program saves the list to disk so I can review it.
However, if the program ...
2
votes
2answers
485 views
DSolve running forever
I have no idea how to speed this up. Does maple do a better job at solving this?
3
votes
2answers
150 views
How to track accumulated error?
If Im not wrong when we use the command N we are using float point numbers in machine precision, right? And the machine precision depends on the bits of the CPU ...
0
votes
0answers
48 views
Errors with NIntegrate: NIntegrate::ncvb and NIntegrate::slwcon
The image shows the array (W) I'm trying to integrate.
It gives the following errors:
1. NIntegrate::ncvb
2. NIntegrate::slwcon
I tried excluding the singularity points; adjusting the accuracy goal, ...
0
votes
1answer
130 views
Plotting of an error estimate of `NDSolve`
So, in an earlier post, (see here), I asked a question regarding a surface of section for a system of coupled non-linear ODEs. What I am after now, is the numerical precision of the results I get back....
4
votes
0answers
201 views
Adding an attribute crashes the system?
At some point I noticed the following errors just in the documentation:
And not only this one, this is not only for Manipulate, there were many others. Also the ...
1
vote
1answer
116 views
What is the best practice way to handle arithmetic exception in Mathematica
What is/are common way/s to handle what would be ArithmeticExceptions in Java in Mathematica/ Wolfram Language? The ugly code is the If...Continues in the innermost For Loop. How should I address this ...
35
votes
2answers
972 views
How do I disable the stack tracing feature in Mathematica 11?
Bug was introduced in 11.0 and persisting through 11.1
It looks like the Mathematica 11 stack tracing feature (see red ellipsis in front of any warning message) prevents the garbage collector from ...
1
vote
1answer
78 views
Catching errors while mapping a solver over a list of parameters
Perhaps this question has a simple answer, I'm sorry but I unable to get my head around it. Here's a minimal description of my issue.
I have a an equation of the form ...
9
votes
1answer
286 views
Unit tests for Graphics or FE boxes
Consider the following expression with bad syntax:
Graphics[{foo}]
How can I detect the error and retrieve the error message programmatically, so I can check for ...
2
votes
1answer
83 views
Plotting function containing NIntegrate: trace the values of convergence problems
Suppose you are plotting a function
Plot[f[x],{x,0,10}]
Where
f[x]=NIntegrate[g[x,t],{t,Tmin,Tmax}].
and when plotting, ...
4
votes
1answer
229 views
How to disable roundoff error tracking in arbitrary precision arithmetic?
In my calculations I need some larger precision. But due to the fact that I iteratively refine the results to compensate for rounding errors accumulated in previous iteration, Mathematica's arbitraty ...
18
votes
2answers
232 views
Would it be a good idea to use Failure and FailureQ in own code
Since version 10 (at least 10.0.2 but I think 10.0.0) there is Failure and since version 10.2 there is also FailureQ. As often ...
4
votes
2answers
172 views
Why do I get number with Precision larger than error estimate?
I'm trying to integrate a large function like this
...
4
votes
5answers
170 views
How to get a list of indices at which errors occur during iteration
I have been looking at some of the questions regarding error handling but i think my problem is unique.
I am running a Do-loop. I get errors only for certain values of the loop variable due to the ...
5
votes
2answers
692 views
Solution of a System of Equations Using `Solve`
Part 1
I am trying to solve a simple system of equations as follows
Solve[{A x^B == f, A y^B == g}, {A, B}]
But I just get the error
Solve::nsmet: This ...
3
votes
1answer
581 views
How to plot a function whose constant parameters have associated uncertainties in Mathematica 8.0?
Let's assume I want to plot the function $f(x)=a + bx+ cx^{2}$, where experimentally known values of parameters $a, b$ and, $c$ are as follows:
$a=1.01 \pm 0.18$
$b=0.92 \pm 0.11$
$c=2.2 \pm 0.2$
...
1
vote
1answer
64 views
Error in the exercise or in mathematica settings
I am going through Kenneth Rosen's book about discrete mathematics. Chapter 1 there is a example where we build functions to check valid conclusions.
Here is the code:
...
4
votes
1answer
232 views
Goal optimization: finding the best combination of capacitors and resistors resulting in given properties
I want to edit @MarcoB answers (because the code he gave doesn't answer the question appropriately)->(the function that need to be optimised is not implemented as asked)
But it seems like I am having ...
1
vote
1answer
170 views
How to count the actual occurence of a warning message in a Do loop?
I am running a lot of simulations to fit a model to randomly generated data. Sometimes the fitting converges properly sometimes it does not, but it will give you the fitting parameters anyway. I would ...
0
votes
1answer
589 views
12
votes
1answer
211 views
Adding Trace produces error messages
This is very strange. As I was trying to debug this problem, I noticed when I add Trace then I get lots of internal errors generated. This also happens the first ...
4
votes
2answers
4k views
SystemException[“MemoryAllocationFailure”, …] with NMaximize
I have a complicated analytical expression that needs to be maximized with respect to a parameter t:
...
4
votes
1answer
109 views
Show error messages from collapsed sections
I've got a fairly long notebook. I like to have most of the sections collapsed. If I evaluate the entire notebook I don't see errors in the collapsed sections unless I expand them. I did see that I ...
5
votes
2answers
354 views
Automatically detect largest interval over which NDSolve can find a solution
Question: Consider the following numerical resolution:
NDSolve[eqn, {x1[t], x2[t], y[t]}, {t, tmin, tmax}
where eqn, ...
1
vote
2answers
154 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
2answers
18k views
How to fix this error : SetDelayed::write: Tag Plus in (<<1>>)[x_] is Protected.? [duplicate]
I don't get the meaning of the sign <<>> and also from which line the error is coming as I have a program of more than 30 lines with many defined functions without using "Module" . Is not there ...
