# Tagged Questions

Questions on optimizing Mathematica code for higher performance. This may mean faster execution, lower memory usage or both. Not to be confused with mathematical optimization.

34 views

### Performance of Apart with complex numbers

Consider the following code ...
76 views

### How to compile code that involve sparse array?

I have the following code ...
145 views

### Fast way to evaluate the PDF of a multivariable distribution

I'm trying to evaluate the PDF of a truncated multi-normal distribution. My distribution has 8 dimensions and each value must be ≥ 0. ...
564 views

### Particles bouncing in a 3D box

I made this Manipulate code which shows a pack of particles randomly moving inside a box. It has a huge performance issue. What should be the best way in doing "...
66 views

### Estimating processing time for commands [closed]

I am trying to evaluate some equations by using Taylor series of expansion (Series[], ExpandAll[], and Normal[] command), and using n equation and n unknown (Solve). Following is not full command (if ...
117 views

### Efficiently strip off coefficients in front of variables?

I am working with multivariate polynomials and need a very efficient way to decompose monomials into coefficients and pure monomials. for instance consider variables ...
170 views

### How I can get faster code for computing a fractional integral?

I use of this code Fractional Integral and wrote the following code: ...
211 views

### Mathematica 10.X benchmark report for high-end surface pro 4/surface book?

Recently, I am seriously considering purchasing the high-end surface device (with intel i7 and maximal RAM). Mathematica will be one of the main applications. Since it is not a full or traditional ...
84 views

### How to speed up the construction of a large matrix

As a part of a physics problem that I'm working on, I need to construct a rather large matrix. The matrix is a real symmetric $2^{m}\times 2^{m}$ matrix for some integer $m$, which we would like to ...
91 views

### Perform matrix/tensor contractions more efficiently

Problem: explicit index contractions for matrices using the Sum command take too long, and I want to improve the performance for complicated computations. Let me ...
206 views

### ParallelTable behaves differently when it is run inside a package

I've been butting my head against some very weird behaviour by ParallelTable, and its interaction with packages, over the past few weeks, and making relatively ...
96 views

### Need help solving a polynomial system [closed]

I need help solving the following system of equations: ...
95 views

### Asymptotic form of the “strange” function

I want to find the asymptotic form of this function ...
108 views

### How to make AppendTo faster

Function AppendTo seems to be very slow for generating a lot of scenarios, is there any chance to change it and make it faster? ...
295 views

### What is the most efficient way to replace items in a list at periodic intervals?

For example, if I want a list of $\phi(n)$ for $1 \leq n \leq 100$ but if $n$ is a multiple of 3 I want to show a 3 instead of $\phi(n)$. I tried ...
43 views

### Finding minima of a function: Ways to speed up the code [duplicate]

I am quite new to Mathematica. I tried to calculate all minima of the function of interest as follows: ...
64 views

### Fast way to compute intersection of equivalence classes

There is a set $S=\{1, 2, \dots, m\}$ and $n$ equivalence relations on the set: $a \sim_i b$, where $a,b \in S$, $i=1, \dots, n$. Now we define $a \sim b$ iff $a \sim_i b$ $\forall i=1, \dots, n$. ...
77 views

### A custom function is too slow when I first time to run it

I make a function like this ...
468 views

I have tried to rewrite my old IDL code to calculate the radial correlation function for a regular 2D crystal structure. The theory behind this function is given here: https://en.wikipedia.org/wiki/...
106 views

### Want Manipulate to be low resolution enough to render fast but no so low resolution that it is useless

When using Manipulate to graph a simple surface (sum of 2 sine waves) with Plot3D, setting PerformanceGoal->"Quality" makes it take about 1/3 second to render, while "Speed" sets it at such a low ...
62 views

### EvaluationMonitor slows down NDSolve considerably

Hi guys I'm solving a nonlinear system of ODEs with NDSolve. Since the dimension of the system ranges from 2700 to 20000 equations, depending on the parameters, the time required to solve the entire ...
95 views

### NDSolve with default settings solves much faster than classic Runge-Kutta 4

NDSolve with default parameters takes 0.25 s for the first run. With Runge Kutta 4 specified, it takes about 4.6 s, ...
143 views