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

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0
votes
2answers
16 views

List of options

It seems this should be easy, by I just can not figure out how. I want to have a function that I can pass a list of options to, or use a default. I have found two very similar questions, but I can't ...
0
votes
1answer
44 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. ...
15
votes
5answers
345 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
53 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
115 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
0answers
41 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
30 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
0answers
102 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 [on hold]

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
46 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 [on hold]

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
42 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
44 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
28 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
96 views
5
votes
2answers
240 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
136 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
424 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
62 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
74 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
93 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
94 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
155 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
240 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
338 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
158 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: ...
4
votes
2answers
79 views

replacement in a nested matrix

We have a nested matrix m1 = {{{1, 2, 2, I}, {1, 1, -2, 1}, {3, 2, 2, -I}}, {{3, 4, 4, I}, {1, 1, 4, 1}, {3, 3, 4, -1}}}; we must replace the first number of ...
0
votes
0answers
62 views

Make smooth plot from data

After some awesome tips from @qwerty I still have some doubts As I said, I´d Like to make a smooth function with some other colors, I plot the graph, there is a lot of data. The situation is this: I ...
0
votes
0answers
46 views

How to get x = 1.234 from {x -> 1.234}? [duplicate]

I'm a complete beginner in Mathematica (started a couple of days ago). I've solved a function using "Solve" and the result is this one: Out[1] = {x -> 0.000942939} How do I get the 0.000942939 ...
6
votes
1answer
320 views

Battery charge simulation not clipping properly as it iterates

My code for simulating a batterylevel-state throughout a year in 15min-steps doesn't work. There is a certain list-inputs which simulates the charge state and the batterylevel-state, additionally ...
3
votes
2answers
108 views

Implementation of a matrix formula

For the Bezier surface, which owns the following matrix definition: where, $B_{n,i}$ denotes Bernstein-basis. ...
0
votes
1answer
128 views

How to make smooth function from data [closed]

After some awesome tips from @qwerty I still have some doubts As I said, I´d Like to make a smooth function with some other colors, I plot the graph, there is a lot of data. The situation is this: I ...
15
votes
5answers
613 views

Easiest/most efficient way to delete duplicates from one list at the positions of another?

This question is somewhat related to How to efficiently find positions of duplicates? , although I'm interested in something a little bit simpler since I'm not really interested in a list of all the ...
0
votes
1answer
33 views

Choosing sets from Subsets[list] part 2

Piggybacking off of this question, say if I wanted to exclude sets which weren't the union of elements of the list of lists. For example: ...