Linked Questions

132
votes
8answers
8k views

Can one identify the design patterns of Mathematica?

... or are they unnecessary in such a high-level language? I've been thinking about programming style, coding standards and the like quite a bit lately, the result of my current work on a mixed .Net/...
70
votes
9answers
56k views

How to find the position of elements in a list satisfying criteria

Say I have a list x={2,4,6,8,10} and I want to find out the positions of the elements that are greater than 7. ...
28
votes
9answers
5k views

Find subsequences of consecutive integers inside a list

I have a list which is something like this: {3,4,5,6,7,10,11,12,15,16,17,19,20,21,22,23,24,42,43,44,45,46} What I'd like to to is get the intervals which are in ...
23
votes
5answers
15k views

How to find the phase difference of two sampled sine waves?

I'm trying to measure a phase difference between two Sine functions I've acquired with a computer. I'm uploading one of the .txt files with the data I'm working with here: txt file. To remove the ...
21
votes
9answers
4k views

Selecting a sublist based on Length

If you have a simple list of lists as follows: test = {{1, 2}, {4, 5, 6, 7}, {5, 4, 3}} How do you ask Mathematica to return the sublist of greatest length? I'...
20
votes
17answers
9k views

Generating a list of numbers that are not multiples of 4

I want to write simple code that will list all numbers from $1$ to $n$ that are not multiples of $4$. And in this case I consider that ...
18
votes
1answer
24k views

Table - find index of the maximum element [duplicate]

Let's suppose that I have table t = {1.23, 3.4, 10, 34, 1.78, 0.98, 12.56}. To take the biggest element I can use Max[t] ...
17
votes
7answers
975 views

How to find all the positions of max value of a list efficiently?

For Example, list=RandomInteger[{1,100},2000]. Yes,I know Position[list,Max[list]] can do. But it's based on pattern matching!...
16
votes
1answer
35k views

Finding the position in a list where the maximum or minimum value occurs [duplicate]

We can use Max[exampleList] or Min[exampleList] to find the maxima and minima of exampleList,...
13
votes
4answers
1k views

I have the minimum Y value. I want to find the corresponding X value from the list [duplicate]

I have a very big file and contains data in the format of {x,y}. I got the minimum Y value by using data[[All, 2]] // Min[#] & Now I want to get the X value ...
13
votes
3answers
1k views

Considerations when determining efficiency of Mathematica code

I have two segments of code that do the same thing and I want to determine the which is more efficient. What are the considerations when determining efficiency of Mathematica code? Correctness/...
9
votes
7answers
1k views

How to pick an element of a row corresponding to the minimum in a particular column?

How can I find what value in column 1 of my list corresponds to the minimum value in column 2?
8
votes
5answers
458 views

Slot # corresponding to subset of a list in select

Is it possible to use # in the select function preserving the structure of the list? Here an example of what I mean. Let's say I want to select all the pairs where the first element is 1: ...
3
votes
5answers
2k views

Minimum in a nested list [duplicate]

I have a nested list of {x,y,z} and I want to find out the values of x and y where z is minimum. I can write a nested For loop and do it ...
3
votes
1answer
1k views

Which integration strategy to use for this product of polynomials?

What would be the ideal integration strategy for a function like this: $$f(x_1,x_2,\dots,x_N)=\prod_{i=1}^Nx_i^{c_i}\Theta(x_i-p_i)$$ where $x_i,p_i\in \mathbb{R}$, $\Theta$ is the Heaviside function ...

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