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

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2
votes
1answer
38 views

Reading an exported List

I have exported a list of 2d coordinates as a List: Export["F:\\coordinates.dat", coordinates, "List"]; You can access the ...
3
votes
2answers
72 views

Plot markers for monthly data

I have the following data ...
4
votes
1answer
74 views

Creating a list of unevaluated pure functions with Apply

Suppose I have a list list with length L and a function ...
4
votes
1answer
86 views

Table with List iterator return unpacked list

Table support list as iterator, for example list1=Table[w, {w, Range[1., 10., 0.01]}]; We can confirm that list1 is packed ...
14
votes
3answers
337 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: ...
1
vote
3answers
114 views

Compute intermediate totals using Select and Plus in a list

I have to total per year of weekly results of a function which are in a table with 3 rows: one with the result of the function, one with the week number and one with the year number. I am almost sure ...
4
votes
1answer
74 views

Is it possible to recover the efficiency of ListConvolve when generalizing the convolution?

I've noticed that, while ListConvolve is very fast, it becomes much slower when you use anything but the standard Times,Plus as ...
2
votes
0answers
42 views

How can I convert some data in TableForm to a list form like as {{0,1}, {1,2},{…,…},…,{m,n}}? [on hold]

How can I convert some data in TableForm to a list form like as So, I have some data there I take from laboratory, but the data has a TableForm 0.0 0.2174 1e-06 0.2178 2e-06 0.2172 3e-06 ...
8
votes
7answers
541 views

Brackets around each item in matrix

I have a matrix where every item in the matrix has its own brackets that I do not want. How can I remove the brackets around each item?
0
votes
1answer
46 views

How to make an empty list inside a module program? It consatly spews errors [duplicate]

Okay, so, I'm trying to write a program within the module. It goes like this: create empty list, join it with a sample from a certain set called MyList, and then repeat it certain number of times. ...
18
votes
5answers
438 views

Partitioning a list when the cumulative sum exceeds 1

I have a long list of say 1 million Uniform(0,1) random numbers, such as: dat = {0.71, 0.685, 0.16, 0.82, 0.73, 0.44, 0.89, 0.02, 0.47, 0.65} I want to ...
1
vote
1answer
57 views

How to refer a number in a list with two columns, first one is a number and the second one is empty? [on hold]

Let's say, I have defined a list as list = {{-31, -31}, {52, }, {34, -11}, {-38, }, {78, -44}, {-36,14}, {-9, 98}, {33, 6}, {82, 99}, {-85, -10}} As you can see, ...
7
votes
1answer
116 views

Add terms to nested list

Suppose I have a nested list of the following: list={{1,2},{5,8},{4,1}...} I would like to add a number to each first term of the list. The output would be ...
2
votes
1answer
89 views

Automatic text-wrapping in labels in `TimelinePlot`

Part-related to this question and part-related to this one, I would like to make use of the new features of TimelinePlot in 10.3, but would like to incorporate some ...
3
votes
1answer
71 views

Calculating products of given length of two matrices

I have the following problem to solve. Let us have two given square matrices $A$ and $B$ of the same size and a positive integer $n$. I would like to produce all products of length at most $n$ of ...
0
votes
0answers
33 views

How can I get a list of the “coefficients” of Quaternion[1, 2, 3, 4]? [duplicate]

I want to input: Quaternion[1, 2, 3, 4] to get a list: {1,2,3,4}.
3
votes
1answer
116 views

Efficiently generating tuples with Outer

I'm trying to efficiently generate tuples of lists of objects that satisfy a given criterion. The similar questions that I have found on this website end up finding a specific workaround for the given ...
1
vote
1answer
33 views

Reverse element in nested list [closed]

Suppose I have a list as the following: list={{1,9},{7,0},{8,6}....} How can I reverse the element in such way that the output would be the following: ...
3
votes
0answers
50 views

Weird behaviour for a vector InterpolatingFunction inside an NDSolve

I have run into some weird behaviour on the part of NDSolve which I find pretty bizarre and which I would like to understand better. Suppose, for the sake of ...
0
votes
0answers
30 views

Group nth Subelement of Nested List [closed]

I'm trying to group the nth subelements of a nested list together. The input would look something like in={ {a,b,c,d}, {e,f,g,h}, {i,j,k,l} } and the ...
2
votes
0answers
44 views

Transposing a table [closed]

I created this table so that it is a collection of 5 different functions that I need. It outputs the values that I want, however, I cannot figure out how to get the orientation right. I would like to ...
1
vote
2answers
45 views

Create an indexed list of functions [duplicate]

I am trying to use a Table to create the following object: {f[#,1]&,f[#,2],f[#,3]} The obvious doesn't work, ...
1
vote
1answer
30 views

How to create sublists of consecutive elements? [duplicate]

I have a list of elements, for example: myList={5, 12, 16, 18, 19, 24, 28, 29, 31, 32, 35, 42, 43, 47, 50, 53, 60, 61, 62, 64, 79, 82, 84, 92, 105, 128, 136, 153, 154, 155, 156, 158, 159, 160, 164} ...
0
votes
1answer
44 views

How to apply a user-defined function to a list [closed]

I'm using Wolfram | Alpha Pro; I have a function f[n] = 351n^(-0.7); How do I apply it to each element of a list like {2, 9, 22}? f/@{2, 9, 22} just results in ...
2
votes
1answer
97 views
5
votes
2answers
241 views

Max of imported numerical data will not work

I loaded a list with 400,000 values from a file. The list was loaded correctly as I can get it's length (by Length[]) and I can also plot it. Why can't I get the Max or Min of this list though? When ...
1
vote
0answers
21 views

Append in For loop doesn't work [duplicate]

I want to simulate a projectile motion under the effect of air resistance by using Append in a For loop, but there appeared to be no changes in the two lists I defined for storing horizontal and ...
4
votes
1answer
137 views

How do I disable that Mathematica orders terms in lexicographic order?

I have matrices with entries where the order of the entries is important. Unfortunately Mathematica resorts terms in products in a lexicographic order. For example, ...
2
votes
1answer
31 views

Encoding/Decoding matrices as integers, integers as matrices [closed]

I want to convert large binary matrices of m x n dimensions into integers, and then to convert these integers to the original matrices. I attempted the following: ...
0
votes
0answers
29 views

DeleteDuplicate from a list with {x == y, y == x} -> {x == y}; [duplicate]

How can I tell Mathematica that it should delete equal elements from a list, which aren't in the same order. For example list={x == y, y == x} ; should become ...
4
votes
0answers
56 views

Create an adequate 'training set' to train a ClassifierFunction which performs the role of the built-in `SubsetQ`

I am trying to "grow" my own SubsetQ function using Machine Learning methods. My cSubsetQ when given two lists (listA and ...
14
votes
3answers
427 views

Generating Tuples with restrictions

I am interested in a certain subset of all tuples. Generating all with Tuples and then filtering is wasteful, and will "blow up" very quickly. For a concrete ...
1
vote
1answer
63 views

Monitoring a matrix with changeable elements as Manipulate in plotting [closed]

If we remember, Mathematica has an ability to show a Psudo-window of plots for monitoring the effects of some changeable parameters in the functions. For example ...
-2
votes
0answers
29 views
2
votes
4answers
55 views

Partition list into sublists of decreasing length [duplicate]

For example, I would like to partition {1,2,3,4,5} into {1} {1,2} {1,2,3} {1,2,3,4} {1,2,3,4,5} with just one line of code. ...
1
vote
1answer
75 views

diagonalization function

If we have a matrix m which is n*n, how can I do mm=U^dagger m U which is a transformation ...
2
votes
2answers
96 views

plotting eigenvalues with devoted level coloring

I am about to plot eigenvalues of a matrix versus varyingj's. ...
2
votes
2answers
91 views

Implementing an affine cipher

I am trying to create functions for encoding and decoding an affine cipher in Mathematica. I have written these two functions: ...
8
votes
1answer
96 views

Duplicate-free results of permutations + constant list

Given a constant list const, e.g. const = {-(15/2), -(13/2), -(17/2), -(15/2), -(13/2), -(11/2)} of length ...
3
votes
1answer
23 views

List of sound objects indexing

I am creating a list of sound objects: tones={}; For[j = 0, j <= 40, j++, tones = Append[tones, Play[Sin[2*Pi*t*500/Exp[-0.1*j/20]], {t, 0, 1}]]]; Each ...
3
votes
2answers
65 views

Assigning multiple solutions different replacement names

Let's say we are solving a homogeneous differential equation, such as $$y^{\prime\prime} + a y^{\prime} + b y = 0$$ with characteristic equation $$s^2 + a s+ b = 0.$$ Using the ...
9
votes
2answers
157 views

Position with test for list of lists [duplicate]

Why do I get this error message? It seems to me that the level specification should have done the job. ...
6
votes
3answers
241 views

How can I create a random symmetric matrix in this way?

The most straight forward way for me to think about is like this: ...
-2
votes
2answers
100 views

How do I write a function that returns the atomic mass given an element's symbol?

I want to write a function atomMass that, given an element's symbol, say "He", returns the atomic mass for the element (in this case ~ 4.0026). I do not even know where to start with this question. ...
8
votes
9answers
339 views

Positions of elements in the initial flattened list in a split list

Say, we have a list: m1 = {2, 2, 7, 0, 7, 7, 2, 2, 2} It can be split easily: ...
2
votes
0answers
17 views

Plotting list of functions while some of them are undefined [duplicate]

I'm struggling with the following code ...
4
votes
2answers
159 views

Subset-type function construction

This is probably a very straightforward thing I am missing, and probably also a duplicate(!), but I can't for the life of me think how to do this cleaner. I want to achieve what ...
0
votes
1answer
30 views

Picking some elements of a matrix and generating another matrix [duplicate]

If we have a nested matrix as: start={ {{1, 2, 2, 3}, {1, 1, -2, 1}, {3, 2, 2, -I}, {1, 2, 0, -I}}, {{3, 4, 4, 0}, {1, 1, 4, 1}, {3, 3, 4, -1}, {1, 1, 2, I}} } ...
0
votes
0answers
59 views

Approaching infinity

I'm using Mathematica to visualize the autocorrelations of all kinds of wave-types. Obviously, my waves aren't infinite and don't have infinite periods though, so the autocorrelation I get is a ...
2
votes
1answer
36 views

wrong result of an iteration related to replacement and comparing

We have two nested matrix and a code for replacement following an equality as: ...