Questions tagged [timing]
This Tag is used for two things: Questions regarding improving execution speed and questions where various methods are compared for execution speed.
144
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Setting shared function values in parallel is running sequentially
I am trying to define a function whose values can be updated across different Kernels running in parallel, where each Kernel might have to use values defined by other Kernels previously in the process....
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82
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Can this loop / code be optimized to find more items in the sequence?
I am looking at the code snippet for OEIS A067075.
Do[k = 1; While[Plus @@ IntegerDigits[k^3] != n^3, k++]; Print[k], {n, 1, 6}]
It does okay for the first ...
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2
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0
answers
61
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Stop NSolve after a certain amount of time and return calculated solutions
I am trying to solve a system of equations of the form:
...
- 225
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0
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71
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Why TimeConstrained does not work when increasing the time?
I found a case where in V 14.4 TimeConstrained hangs when increasing the time from 60 seconds to 120 seconds.
This happens only in V 14.0. Same exact code works in ...
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2
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0
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79
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Abnormally long computation time using AppellF1 function
I am trying to use the AppellF1 function in Mathematica 13.3.1 on an Ubuntu machine with an i7 13700. The inbuilt function seems to be much slower in some cases ...
- 66
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74
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Can we explain why Timing is inconsistent?
I am trying to speed up a code and by placing Timing statements in the code I identified a suspect calculation that I do repeatedly. In order to test out the ...
- 16.7k
1
vote
1
answer
160
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Creating and printing a real-time evaluation timer
I want to print a timer that starts at 0 when an evaluation begins and stops when the evaluation is completed. I have come up with the following solution using Clock...
- 13
2
votes
1
answer
82
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CPU time in iteration process
Let $Tx=\frac{x}{2}$ for all $x\in[0,1]$. Let $x_{0}\in[0,1]$ and set an iterative sequence $\{x_{n}\}$ by the method $x_{n+1}=Tx_{n}$. Now if $x_{0}=0.8$, then I get a convergent sequence towards the ...
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3
votes
2
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127
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Position command runs much slower for range containing numerically evaluated Bessel function
I have a long list (about 10000) of positive numbers (here simply denoted list), for which I want to find the positions of elements lying between 0.5 and the first ...
- 1,043
13
votes
3
answers
506
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Why does Module slow down StringMatchQ by 180 times?
I knew that Module is slower than With or Block, often by several times. But it surprises me ...
- 2,569
3
votes
1
answer
52
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Inconsistent Timing on FinancialBond valuations
I need to do bond valuations (lots of them across lots of data) using FinancialBond.
Context & Background
I have daily interest rate data on 30 year US Treasury ...
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1
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165
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How do I speed up this numerical integration with Bessel functions? (Tried changing Working Precision and Integration Strategies)
I need to compute the function P[b] given as follows:
...
- 11
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41
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Derive a function and then make a fast version for execution
I would like to derive a (complicated) equation of motion and integrate it efficiently numerically. I can do this "by hand" by copying the resulting function in a new function and then ...
- 323
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votes
1
answer
151
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Inverse taking no time? [closed]
I was comparing the time that the computer takes to perform Partial Pivoting, Total Pivoting and multiplying by the inverse. The code (that makes the comparison chart) is as follows:
...
- 107
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0
answers
94
views
Solving an equation without output
Could you please help in solving the equation below. I am not able to do it with the current version of mathematica (very old one). All parameters are real and positive.
Thank you so much in advance
<...
- 21
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73
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Is there any hope to compute the determinant of $56\times 56$ parametric matrix and simplify the result?
I have this $56\times 56$ parametric matrix $M$ and I want to compute its determinant where $\{t,y,z\}$ are some real parameters. I use Det[M] but it takes a lot ...
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6
votes
1
answer
188
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Why does Table take so much longer than its constituent computations?
I have a 10x5xn list, which I'll call data,
data = RandomInteger[{-500, 500}, {10, 5, n}];
...
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11
votes
2
answers
411
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Speeding up time in computations: a visual and easy way to find the slowest parts of a code
[
Edit 2:
The resource function TraceView gives a nice way to visualise the timing. This Resource function is also mentioned here :
https://mathematica.stackexchange.com/a/278723/86543
]
[
Edit: I ...
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1
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77
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Why the performance of list of Timings depend on the order?
It seems that the result of list of Timings and AbsoluteTimings depends on the order, while ...
- 2,569
4
votes
1
answer
44
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Timing Discontinuity with Replace[] Function
When constructing certain square matrices I noticed a sharp jump in the time required to build them. I've included code and a plot of time required to make the matrix vs dimensionality of the matrix. ...
- 187
4
votes
2
answers
90
views
Format Time Reported by AbsoluteTiming
I am trying to format the timing reported by AbsoluteTiming so that it states the hours minutes and seconds of the result. However, probably because ...
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5
votes
1
answer
128
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Why the coefficient function is very fast
When looking for the coefficients of an desired series, I found that the Coefficient function is very fast compared to other functions and methods.
In the following summary, we find the different ...
3
votes
1
answer
74
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Defined function takes more time than pure/anonymous function. Why? [duplicate]
A function defined by f[x_]:=<code> and applied on every element of a list as f /@ testList seems to take longer than the ...
- 321
1
vote
1
answer
149
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Explicit integration of PDE running very slowly
I would like to solve the PDE $\frac{\partial u}{\partial t}=(1-x)\frac{\partial u}{\partial x}$, in the interval $[0,1]$, with initial condition $u(0,x)=e^{-218(\frac{-2}{3}-ln(1-x))^2}$, by manually ...
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70
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Why is Clip so slow and how can I improve its performance?
The built-in function Clip is defined as a way to clip a value between a specified minimum and maximum. Another way to do this, is simply by utilizing ...
- 952
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vote
1
answer
65
views
How to get correct note timings when importing multi-track Midi files?
I have observed when importing midi files with more than one track, the times for every track except for the first one are sped up.
for example,
...
- 1,078
-1
votes
3
answers
172
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Elimination of the variables
I am trying to get an equation in terms of variable z by eliminating variables g0 and g1 but
Running below code is taking time forever
...
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1
vote
1
answer
82
views
Using With[] vs. Using a Pure Function for Constants
There are many cases where I am conflicted over using With[] versus using pure functions when dealing with constants, knowing the output is the same either way. For ...
- 1,627
4
votes
4
answers
320
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Code to solve quadratically constrained quadratic optimisation problem using FindMinimum is very slow. How do I make it faster?
The problem
I have a quadratically constrained quadratic optimisation problem (QCQP) which takes about 13 seconds to find the optimal solution. I want to iteratively optimise a large number of times (...
- 245
1
vote
2
answers
137
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How to make the following code work faster?
The problem
I would like to compute the Lorentz transformation $\mathbf{p}'$ of an arbitrary 3-momentum vector $\mathbf{p}$ given a boost characterized by some other momentum vector $\mathbf{p}_{N}$, ...
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6
votes
4
answers
181
views
Check if list is singleton in sub linear time
A singleton is a list whose elements are equal. Some ways of checking this in Mathematica:
{Equal@@#&,
1==Length@Union@#&,
MatchQ[#,{x_ ..}]&}
I ...
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66
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How to evaluate the following integral faster?
I have a problem with the time required for evaluating the multi-dimensional integral and would be grateful for any help in reducing this time.
First of all, there are some pre-definitions used in the ...
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3
votes
1
answer
164
views
Why Dot product of my vectors takes longer than usual?
I have a list containing 100 complex numbers lying between 1.9 + 1.9 i and 2.0 + 2.0 i
you can download its mx file from the link below and import it in Mathematica:
http://adambarfib.ir1.rapidpars....
1
vote
0
answers
57
views
Long execution time using position
I have two lists, for example:
List1={2,4,6,8,10,12}
List2={4,10,12}
I want to find the positions in List1 such that the element at that position is equal to the ...
- 107
1
vote
0
answers
71
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How to reduce the computation time of this series expansion?
I have a complicated function gg[Delta,l][z1,z2] which is given in the sample code below. I would like to expand this function for as many ...
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votes
0
answers
54
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Why is doing a computation inside Select slower than a precomputation?
I am trying to generate primitive Pythogorean triples using Euclid's parametrization. I basically want a list of pairs with ordered pairs $(m,n)$ such that $m$ and $n$ are coprime.
My first approach ...
- 161
4
votes
1
answer
175
views
Multi-dimensional array lookup vs flat array lookup with compute
During Monte-Carlo (MC) simulations on a latice of dimensions $(L_1,L_2,\ldots,L_D)$, all the site varibales are often stored as a $D$ dimensional array array. To ...
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3
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2
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131
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4
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0
answers
56
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Difference in computation speed of Eigensystem not to expectation for ParallelTable and Table
I was trying to compute the time it takes for Eigensystem to evaluate while being inside a ParallelTable, as it is well-known LAPACK subroutine has an inbuilt Parallelization to it. And the difference ...
- 613
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votes
1
answer
29
views
Calculation time differs between segmented loops and one whole loop
I stumbled on a strange issue while simulating a large number of random values, $10^8$ to be precise.
I generated the numbers at first by the following code:
...
- 127
4
votes
1
answer
240
views
Reduce the time of computation for $5$-dimensional numerical integration
I need to perform (numerically) the $5$-dimensional integral given in the code below for a large number of values of $\epsilon$. The code I have at the moment takes $\sim 11$ minutes and returns an ...
- 711
9
votes
0
answers
839
views
Mathematica 12.1 start-up time in Linux extremely slow
I installed Mathematica 12.1 on my Linux machine and the start-up time is extremely slow.
I see the Spikey logo and messages like:
Initializing Kernel connections
...
- 1,201
2
votes
0
answers
46
views
Summing Kronecker Deltas: Sharp slowdowns for simple sums
I'm using Mathematica 12.0 Student Edition. I'm a little confused by the length of time Mathematica takes to evaluate certain sums of Kronecker Deltas or Discrete Deltas. Here's a simple example below:...
- 247
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vote
1
answer
86
views
Converting Timing to TimeObject
What's the proper way to get Timing and post-process it for example to convert to a TimeObject as a defined function?
In line, ...
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1
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0
answers
65
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Filtering Fibonacci numbers for elements meeting certain criteria [closed]
Write a code that selects in less than two seconds from every 123rd of the first 33,333 even Fibonaci numbers; those which contain the digits 2, 3, 6, 7, and 8 and also contains the digit 1 more than ...
- 11
2
votes
2
answers
198
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How to set a timer (countdown) in Manipulate what stops it running?
I have a Manipulate function with 2d slider which I can play with some curves. I consider this as a game (gamification in physics). I want to set a timer so when it countdown to zero then the game ...
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votes
0
answers
103
views
How to speed up Timing[4^(10^10)]
I have an old computer with a quad-core AMD Phenom II processor (3Ghz). When I run Timing[4^(10^10)]the computer takes hours to evaluate the expression. I'm not ...
- 101
2
votes
1
answer
322
views
Using Parallelize in a solve function
Is there a way to use Parallelize the following operation, in order to make it do the calculations faster? Or is there another way to speed up this calculation?
...
- 2,021
1
vote
1
answer
85
views
Generalization of code is slower than particular case
I wrote the following Mathematica module:
...
- 153
2
votes
3
answers
114
views
Summing all the times of a column
It is possible to add a last row in the table where I can show the sum of values of the last column. I would like to get the total time value...
...
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