Questions on the sorting/ordering functions of Mathematica (Sort, SortBy, Ordering, etc.).

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3
votes
5answers
266 views

Ordering the Boundary points of a Polygon

I feel like this should be simple, but I keep running into walls. Say someone gives you the coordinates of the vertices of a pentagon and the center point of the hexagon. Is there any way to get an ...
3
votes
3answers
151 views

Properly ordering the output of FileNames for a directory consisting of files with consecutive integer names [duplicate]

Say I have a number of files in a directory at some location (C:\dir1\dir2\dir3...), and I pull an array of strings corresponding to the file names with the command: ...
3
votes
2answers
157 views

How to define even permutations correctly?

I define even permutations as following, but there may be some error. I use it in two different way and get different output. ...
3
votes
1answer
67 views

Order imported files by their alteration date

Probably a very easy question, but I could not find the answer, so it would be very nice if you can help me: Let us say I have 10 files, all with the extension ...
3
votes
2answers
460 views

How to plot several functions without jumping? (multiple eigenvalues of a system as functions of 2 parameters)

I've been working on this research problem for months with some success by no global/proper solution to the problem. So I have square, Hermitian matrices of various sizes ($8,20,38$ dimensions) with ...
3
votes
1answer
194 views

Windows Explorer Natural Order

Currently there are a list of notebooks in Windows that I am processing in a folder. Ideally I would like the notebooks to be concated in the same order as how they display in Windows Explorer. I ...
3
votes
2answers
108 views

Non-canonical re-ordering of nested lists

I have some data in the form: ...
3
votes
1answer
34 views

Multicolumn sorting with ordering functions and precedence

I am aware that the question of "how do I sort on a column" has been asked in various forms, most notably this one. While some powerful solutions have been presented, as far as I can find no one ...
2
votes
2answers
250 views

Position function not always retuning an answer even with no apparent problems

I'm having some problems with Position. Sometimes it will give an empty list instead of the actual position of the element I am looking for when that element is ...
2
votes
3answers
294 views

Re-arranging / selecting of a data table very slow in For loop [duplicate]

My task is quite simple; I have a table of data like M = {{1,2}, {1,3}, {3,4}, {5,1}, {6,9}, {6,8}, {6,1}}; so the table is sorted with respect to the first ...
2
votes
1answer
108 views

Confused behavior using Dispatch to sort one list relative to another

I have a need to sort the entries of one list into the same sequence as the entries in a reference list. Because I have rather large lists involving strings, I'm trying to use Dispatch to accomplish ...
2
votes
1answer
90 views

How to get the ranked order

data = {33, 6, 10}; Ordering[data] (* {2, 3, 1} *) What I really want is, 3 for 33, as it is the 3rd, if sorted; 1 for 6, as it is the 1st, if sorted; and 2 for ...
2
votes
1answer
283 views

Rank functions of n by their order of growth

I'd like to rank some functions according to their order of growth (e.g. n^2 < n^3). I'm not sure how to do order of growth in mathematica, so I was trying to ...
2
votes
1answer
360 views

How do I sort complex numbers?

Okay, so I posted something about sorting, and it was linked as a duplicate to This post However, I am having problems trying to sort a list that contains both real and complex numbers. I put them ...
2
votes
1answer
63 views

Sorting a matrix except its last row

Given M = {{"Utah", 2}, {"Iowa", 1}, {"Maine", 3}, {"Total", 6}} I want to obtain the reverse-sorted result like this: ...
2
votes
3answers
81 views

Comparing two lists lexically

I have two lists of integers a and b of equal length, and I would like to define a>b as ...
1
vote
2answers
184 views

Sorting lists element by element [duplicate]

I have a problem regarding list sorting. Let's say I have a list of lists obtained using Subsets[], of the form ...
1
vote
2answers
81 views

Sorting lists with elements that are identical [closed]

How can I sort the following list: list={{1498, 1495}, {1498, 1733}, {1553, 1552}, {1552, 1495}, {1733,1776}, {1776, 1553}}; such that the next group contains ...
1
vote
2answers
171 views

How to sort Table/Matrix including legend(Labellings)

I want to sort table including its legend for graph I have table similar to M1 M2 M3 1 5 2 3 1 4 4 2 -10 5 7 11 6 -2 1 ...
1
vote
1answer
236 views

How to Sort on row by row basis?

Say I have matrix how to sort on row by row basis to get:
1
vote
3answers
46 views

While subpartitioning the elements in list using GatherBy, can I corresponding subpartition the elements of an unrelated list?

If we have a list like the following: list1 = {1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12}; And we use GatherBy to subpartition is according to a test function ...
1
vote
2answers
127 views

How to sort the adjecency matrix of bipartite graph so to have two off-diagonal blocks

In a bipartite graphs there are two class of nodes, say A and B. Each node of class A may interact only with nodes of the class B, and viceversa. The corresponding adjecency matrix is thus composed by ...
1
vote
1answer
49 views

Disabling Mathematica's automatic sort of output

I used Mathematica to greatly simplify an algebraic expression. I now want to copy it into some notes, but it by defaults things in a very non-intuitive manner. I have a sorting function that will ...
1
vote
1answer
83 views

Sort lists of vertices {indegrees, outdegrees} by indegree

in = VertexInDegree[F]; out = VertexOutDegree[F]; I want both in and out to be ordered by in. Example: graph has nodes a,b,c with indegrees 1,2,0 and outdegrees ...
1
vote
1answer
58 views

How can I sort the polynomial by the degree of $x$

f1 = a x^2 + b x + c + x^3 (* a x^2+b x+c+x^3 *) f1 /. x -> (x - a/3) // Expand (* (2 ...
0
votes
3answers
86 views

Place symbols from small to big

I am wondering how to compare the different values of ω I derived in this code, and place them in order as follows. (use Print ...
0
votes
2answers
54 views

Sorting non-numerical lists [closed]

The Sort function will by default sort from lowest to highest. In[1]:= Sort[{3, 1, 4}] Out[1]= {1, 3, 4} However, if the list ...
0
votes
3answers
63 views

Complement[] changes order of elements?

Consider this example: Complement[{a, y, c, d, e}, {a, c}, {d}] (*{e, y}*) However, I was expecting the result to be: ...
0
votes
1answer
84 views

Problem with Sort - unexpected order with Sqrt [duplicate]

Sort[{13, Sqrt[157], Sqrt[163]}] (*{13, Sqrt[157], Sqrt[157]}*) Sort[{13, Sqrt[157], Sqrt[157]}, #1 < #2 &] (*{Sqrt[157], Sqrt[157], 13}*) This seems ...
0
votes
1answer
154 views

Using Sort vs SortBy

So I have two lists, A and B. I put them into lists = {A,B}I want to sort A such that Im[#1]<Im[#2]& which I can do fine ...
0
votes
1answer
81 views

Ordering under assumptions

I have a three-element list which contains inverses of a function u, like so: ...
0
votes
1answer
133 views

Sorting a list of triplets by first element of each triplet fails

In the last line of code, I´m trying to order the matrix by the first column. I want to store in the Array t2tlistsorted ( 100 x 3 ), but I can´t. ...
0
votes
1answer
43 views

Sort a multidimensional list row-wise [closed]

Suppose I have a multidimensional list as shown below: RandomInteger[{1,10},{3,7}] I obtain the results: $$ \left( \begin{array}{ccccccc} 3 & 8 ...
0
votes
1answer
67 views

Sorting a table of vectors with weights [duplicate]

I'm trying to simplify a table, for instance {{1, {4, 2, 0}}, {4, {2, 4, 0}}, {-2, {3, 3, 0}}, {1, {3, 0, 3}}, {-3, {0, 4, 2}}} Here the first column is the ...
0
votes
1answer
105 views

Sorting lists of lists with string elements [closed]

I have a list of sublists. One element of each sublist is a string element. For example: list = {{1, "banana", 3}, {3, "orange", 1}, {2, "apple", 2}}; When I ...
0
votes
1answer
66 views

Produce a 1-dimensional list of all unique matrix elements

We have some symbolic matrix m, e.g. m={{1, x, 4 x + y},{0, x y + 4x, 4x},{7 x, x, 4x + x y}} and we want to produce as output a list of all the unique elements ...
0
votes
1answer
99 views

Another Sort with multiple criterion

I have a list ...
0
votes
0answers
53 views

Ordering oscillators with negative powers: Infinite loops

I have been working with ordering of oscillators for example $[a,a^\dagger]=1$ and I have a fairly stable code. I have needed to use inverse oscillators for example expressions like $a^m ...
-1
votes
1answer
103 views

Sorting the element in a PDB text file

I am a new user of Mathematica and currently using version 9. I want to rearrange the element of one PDB text file with respect to another PDB text file. Suppose I have a PDB file like this: ...