Questions on the manipulation of List objects in Mathematica, and the functions used for these manipulations.

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4
votes
3answers
118 views

Alternative forms to Table for iterating over replacement rules

I have a multivariate polynomial x. I get coefficients of various monomials using CoefficientRules, which returns a list of ...
-1
votes
3answers
75 views

Create table of elements which belongs to specific sets

I would like to produce elements (preferably by Table or For-If commands) that they belong to specific sets. For example I want to write positive integers from 1 to 100 such that they are $2 \pmod 3$, ...
1
vote
1answer
82 views

How to determine distance of periodic features in measured dataset

I have a list of x- and y-values associated with a measured height (z-values). Part of the list is plotted below. As you can see, there is a periodic arranged structure, namely a cross. Now I would ...
-6
votes
0answers
53 views

rename files randomly

I need to read a directory with pdf files, rename them by numerical sequence of 8 digits when lifting with pdf extension, and then record the result (the idea is that they are totally random names ...
9
votes
1answer
189 views

Fast implementation of Metropolis-Hastings update with multiple sets

This is an optimisation question rather than something I am unable to do. I have a naive, primitive working version of the code (I submit it below) but I am trying to make it work faster. I am asking ...
2
votes
3answers
232 views

How to use Select with lists

I am trying to do: Select[minimus[[6]], #1[[2]] < (min[[6]] + emin[[6]]) &] applied to all elements of minimus, ...
0
votes
0answers
27 views

factoring a phrase of matrix elements and calculating main eigenvalues

I have a question containg two parts: 1-If we have a matrix as ...
15
votes
9answers
617 views

Any built-in function to generate successive sublists from a list?

Given lst = {a, b, c, d} I'd like to generate {{a}, {a, b}, {a, b, c}, {a, b, c, d}} but using built-in functions only, ...
5
votes
3answers
269 views

Indicate minimal path sum

Described on the page: http://www.mathblog.dk/project-euler-81-find-the-minimal-path-sum-from-the-top-left-to-the-bottom-right-by-moving-right-and-down/ It is an example of the solution indicated in ...
0
votes
1answer
47 views

How to pad numbers to the border of the Matrix?

I want to pad the numbers,but it throws an error Part::partw,so I use Quiet to suppress this error. ...
3
votes
1answer
68 views

Calling results of applying f to expr inside NestList

Being new to Mathematica, I try to follow the suggestions of using NestList, Map, Table ...
5
votes
1answer
39 views

Heading in Table Form Question

I have: modadd = Table[Mod[i + j, 3], {i, 0, 2}, {j, 0, 2}]; TableForm[modadd, TableHeadings -> {{0, 1, 2}, {0, 1, 2}}] Which produces: How can I put a ...
3
votes
1answer
185 views

Minimize sum of array elements subject to conditions

I have array where each point at different times are shown parameters ...
0
votes
4answers
50 views

insert elements into 2 D array [duplicate]

say I have a 2 dimensionsal array like a={{1,2,3},{4,5,6},{7,8,9}} and a vector like v={10,11,12} I want the result to be ...
4
votes
1answer
102 views

UpTo for negative indices?

The symbol UpTo emerged as a sort of "safe take" in version 10: Take[{1, 2, 3}, UpTo[4]] (* Out: {1, 2, 3} *) But it wasn't ...
6
votes
2answers
330 views

Performance of calculation of means squared displacement

How can I improve the performance of the following code which calculates the mean squared displacement for coordinates stored in data? Here for each time difference ...
7
votes
2answers
94 views

For loop works at top-level but not in a function

Why does this work: For[i = 1, i <= Dimensions[list][[1]], i++, list = Insert[list, i, {i, 3}]] But this doesn't: ...
2
votes
2answers
73 views

Group Datasets and take minimum/maximum

Good Morning I have the following dataset: And I try to reach this output: key: only one row per key text: join all texts of the rows with the same key (but no duplicates) min: take the lowest ...
3
votes
2answers
78 views

Generating a sequence of lists [closed]

I have learnt how to generate a sequence of numbers, but now I come across a question whether it is possible to generate e sequence of lists. Say, I would like to generate ...
8
votes
3answers
341 views

Give a element rank list of a list

SeedRandom[417] list1 = RandomChoice[Range[22, 28], 4] {22, 24, 26, 23} We can get the rank list ...
1
vote
1answer
50 views

Rearrange the list with some rules

I am trying to solve physic problem on operators which are not commute. However, I am not good at coding, so I am having some problem with Mathematica code. Let's define my list such that ...
4
votes
2answers
106 views

`IntegerPartitions` without duplicates

I need to apply a function to integer partitions of many integers, but only the partitions without duplicate numbers. Select[IntegerPartitions[n], DuplicateFreeQ] ...
0
votes
2answers
62 views

How to prove that an equation can be divided by any n?

I'm new to Mathematica and came across with the problem. I can't prove that (for example) 2*n is always even no matter what n ...
0
votes
1answer
89 views

How to turn a subroutine into a function?

I've written a subroutine that takes in 6 matrices and after some manipulation returns back 3 new ones. I will use this subroutine fairly often in this notebook so I think it would be easier to turn ...
-1
votes
1answer
46 views

How to graph the max and min values of a sheet?

Hi I just start working in Mathematica version 10.3.1 and I want to graph a sheet of data that I created in Excel (yeah i use Windows). The problem is i have so many data; 200 columns and 50 row of ...
11
votes
2answers
407 views

How to fill a grid make its total be largest

I have a blank grid whose dimension is 5*5. I want to fill it with some number using 1, 2, 3 and 4. But in every blank space if you fill 2, its neighbor (include four direction, such as left, ...
-1
votes
1answer
41 views

Generate list of first 100 prime number? [closed]

I know how to generate a list of prime numbers up to a limit, but how would I generate the first 100 prime numbers in a list?
3
votes
2answers
96 views

Using “Outer” with “ChineseRemainder”?

I'm looking to build a $7\times3$ matrix using ChineseRemainder. Trying to use ${0,1,2,3,4,5,6} \pmod 7$ and ${3,15,21} \pmod {30}$ so that the first element of ...
0
votes
0answers
57 views

ListDensityPlot3D with discrete user data [on hold]

I have a ext file with 7 columns and 5.000.000 lines (a trajectory file for a particle in 3D). After normalizing position vectors for each frame to norm 1, I basically obtain a list of three ...
4
votes
3answers
127 views

Replicate sublist in new list

If I have a list of lists $a$ and a list of occurrences of each sublist $n$ a={ {1,1,1}, {2,2,2}, {3,3,3} } n={1,3,2} what is the most efficient way to get the ...
3
votes
2answers
68 views

Calculate Cumulative Mean and Standard Deviation of a list without FOR loops [duplicate]

I have a simple list mylist={x_1,x_2,...,x_N};. Now I want to map a function over this list, e.g. the Mean and StandardDeviation functions, so that it will give me ...
5
votes
3answers
121 views

How to partition a set with a condition on subsets?

I want to partition a set of $n$ elements into $k$ subsets with a condition For example: partitioning this set {1,...,5} into 3 subsets with this condition: if $|i-j|<d$ then $i$ can't be with $j$ ...
16
votes
3answers
431 views

How to group and join points

It seems there are many similar questions on Mathematica.SE, but none addresses (to the best of google) exactly my problem. I have the following data: ...
0
votes
1answer
51 views

Append[] is not working for empty list [duplicate]

I am trying to create an empty list and add an element but the list is not being populated. My code ...
0
votes
0answers
39 views

Do[If[ *stuff* ]*arguments*]: Increasing range over which Do iterates changes results of If?

Summary: If I run the same Do[] expression but with the variable(s) over which I am iterating taking on more values (but same increment), an If statement inside the Do[] evaluates as false a few times ...
0
votes
1answer
48 views

Interactive Application using Manipulate for Fibonacci Series

I am working on creating interactive app using Manipulate function on fibonacci series using SeriesCoefficient. I want to plot the fibonacci numbers based on the slider of Manipulate function. I ...
26
votes
6answers
4k views

How to Delete Elements from List1 appearing in List2?

I'm new to functional programming of Mathematica and trying to remove one list of assorted elements from another. However I only find functions working with the Index rather than the values itself: ...
0
votes
1answer
41 views

Help with limiting output

I wrote this program on Mathematica (which I am very new to): ...
11
votes
4answers
481 views

How do I extract a matrix of only positive numbers given a set of assumptions?

I want to divide a matrix: mat = {{a, 0, -b}, {d, a, 0}, {0, 0, -a}} with the following assumptions: ...
10
votes
4answers
263 views

Convert elements of list to string

how easily can I convert elements of this list to string. If I have output like this: {{M, 1, 0, 0, 1, 1, 1, 0}, {A, 0, 0, 0}} And I want something like this: ...
0
votes
1answer
74 views

ListPlot and Show n plots from two lists with large n

For the context, I have been dealing with Random Matrices and Dyson Brownian motion. I have two lists, the first one contains the number of steps, so ...
5
votes
2answers
310 views

How to construct a dataset with lists as columns

So I know this should be pretty easy, but I cannot seem to find a solution anywhere, so thanks in advance for your help: I have three Lists (with numbers as ...
1
vote
0answers
50 views

Estimating processing time for commands

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 ...
8
votes
3answers
559 views

Finding all sublists or substrings of a given list/string

Given a list or string, how do I get a list of all (contiguous) sublists/substrings? The order is not important. Example for lists: ...
-1
votes
1answer
87 views

Lattice model array for distribution of energy [closed]

Edited for clarity I am trying to make a 2-D array constant, lets say 100x100, and perform a function on that. The array would look like ...
6
votes
3answers
169 views

How to prevent substitution in a part of an expression?

Background: I am trying to write a program that can execute scheme in Mathematica. Now I have things like {"+", 3, {"-", 2, {"'", {"*", 1, 3}}}}. The syntax ...
0
votes
2answers
54 views

RSolve - basic question about using rules as functions

I think this is basic question, but I can't find it in Help... (I am begginer :P) I have this expression ...
5
votes
5answers
271 views

How can one get all possible sublists of a list? [duplicate]

So if list={1,2,3} then output should be {{},{1},{2},{3},{1,2},{2,3},{1,2,3}} or in different order.
2
votes
2answers
182 views