# Tagged Questions

This Tag is used for two things: Questions regarding improving execution speed and questions where various methods are compared for execution speed.

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### Is it possible to use a function for EdgeWeight in a Graph?

Why I cannot calculate all edge weights beforehand: I have many large graphs for which I'd like to find the shortest path between two vertices (FindShortestPath ...
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### Syntactic Sugar for TestReports

Seems to me that VerificationTests are a bit verbose: ...
219 views

### Getting AbsoluteTiming to display in hours, minutes, and seconds

I'm doing some extended length calculations and was wondering how I could get AbsoluteTiming to display in hours, minutes, and seconds. I googled and found nothing, ...
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### Timing and ListPlot

I am currently trying to examine the Timing function as it relates to generating primes and factorize large integers. What I want to do is to visualize how time ...
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### frequent slow evaluations for trivial expressions, large memory loaded

After loading a lot of data into memory and evaluating several hundred expressions without any problems, trivial expressions such as (1+2) take about 5-10 seconds to evaluate. Sometimes they are fast,...
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### How can I pass arguments to Module without being reinterpreted each time they appear inside it?

I'm trying to understand how to save time when calling functions in Mathematica. I wrote this example, ...
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### Problem with Conditionals: Why does mathematica add an extra empty list to my output

I have a set of positions where I want to slice a list of numbers. If I Total the values in that list, and they are greater than or equal to 1, I want to remember ...
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### Evaluation time is always 0.23 s [closed]

Following the instructions in this documentation page, I'm setting EvaluationCompletionAction -> "Show Timing" in the option inspector so that Mathematica prints ...
299 views

### Incorrect Timing of Total

For demonstrating how fast C-compiled functions can be, in one of my courses I use the following function for finding the sum of a list of reals: ...
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### Why does Timing return different times for the same calculation?

I did an experiment in which I calculated the same quantity two different ways to see which method was faster. To my surprise, the kernel time was different in different runs. In fact, which method ...
281 views

### Good coding for a sequence of derivatives

People on this site keep telling me that good MMa practice avoids the use of loops. The code below calculates the same Table of derivatives two different ways, ...
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### Differences in AbsoluteTiming for similar codes

Consider the two following codes with the same SeedRandom (which ensures the same set of random numbers) but different use of the ...
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### Why is this function taking so much more time when its argument reaches 250? [duplicate]

I am observing something which I do not understand with the following function function: ...
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### Timing of associated Legendre polynomials

I encountered a strange issue with the associated Legendre polynomials implemented with LegendreP[l,m,z]. Quite simply, the time used for the numerical computation of those quantities depends on ...
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### Calculating a multiplication of large number of matrices takes a long time [duplicate]

I have a multiplication of matrices, say M1.G1.M2.G2.....Mn.Gn, here n may reach 100. M and G are 4 4 matrices and their elements are function of s. Mathematica takes so long to perform this ...
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### Optimization of custom probability distibutions?

Consider the two tests: Timing[Do[RandomVariate[NormalDistribution[0.5, 0.3]], {200}]] {0.001188, Null} ...
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### Reflecting lines in ellipses: speed up the code?

I have the following code which calculates a list of points that a line would take after bouncing off various ellipses. ...
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### Is Daylight Savings Time accounted for when using AbsoluteTime[]? [closed]

I have been running rather long computations lately and timing them using AbsoluteTime[] by calling it at the start and end of the computation. ...
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### Function takes hugely different times to evaluate on sets of virtually (but also literally) identical data

I'm experiencing something which I believe to be weird with a function that I wrote. Briefly: what happens is that I generate random data to feed my function in two different but equivalent ways (...
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### Strange timings of integrals involving Hermite's polynomials

I have used Mathematica to calculate tunneling for quantum harmonic oscillator. The code is simple: ...
163 views

### Timing mathematica code

I have a collection of functions (Modules) and I wish to find out which sub-routines inside the code take up most time. I have done this by wrapping individual code blocks with ...
158 views

### How to determine how much time it will take to finish a cell expression?

I am trying to integrate a large matrix with elements that contain trigonometric expressions. The evaluation is taking a long time--4 days, and it is still running. Is there anything I can do to find ...
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