Questions tagged [sorting]
Questions on the sorting/ordering functions of Mathematica (Sort, SortBy, Ordering, etc.).
424
questions
2
votes
2
answers
74
views
Implementing HeapSort in WL
Good day,
I am trying to implement the HeapSort Algorithm using WL. My attempt is shown below.
...
- 111
5
votes
5
answers
642
views
How to sort filenames in actual numerical order?
I have inherited a collection of files that are numbered... something like:
file-0, file-1, file-2, ... file-9, file-10, file-11, ... file-19, file-20, ...
When I Import them, they come in scrambled ...
- 68.3k
3
votes
1
answer
95
views
Range of values which not satisfy an equation?
Let $$x+5=z\tag1$$
1. How can i obtain all the values of $0<x<10$ which don't satisfy the given relation. Edit: of course $x$ and $z$ are positive integers.
2. What command should i use to find ...
- 33
1
vote
1
answer
90
views
Writing a function that sorts by low powers while ignoring higher powers of various variables
I'm writing a Mathematica code with the aim of automating operator mixing calculations in QCD (at least at one-loop order). So far, it can generate Feynman rules and all graphs, assign the rules, call ...
- 21
2
votes
3
answers
192
views
Sorting a list of lines such that they are successively connected
I have a list of line segments of the form $\{u_1,u_2,\cdots,u_n\}$, where $u_{k}$ is of the form $\{\{a_k,b_k\},\{c_k,d_k\}\}$. I want to sort them as $\{v_1,v_2,\cdots,v_n\}$ in such a way that Last[...
- 799
3
votes
2
answers
216
views
How to sort a list of colours and assign it to four categories?
I have a list of colours with RGB values like this :
...
- 105
3
votes
2
answers
189
views
4
votes
1
answer
114
views
Sorting by SortBy without converting to numerical values
First output returned by Sort is correct - ordered from smaller to bigger numbers.
Second output returned by SortBy is correct ...
- 9,923
8
votes
4
answers
314
views
Double sorting by two criterions using Sort
I was sorting a list of pairs of numbers firstly by second number then by first number. I wanted to use Sort since we can use #1 ...
- 9,923
5
votes
6
answers
326
views
Restrict sorting to a certain range
Example data (revised to include negative values - see comment of @ydd)
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- 48.9k
4
votes
4
answers
243
views
How to confirm two sets contain the same vectors in any order?
Say if I have two sets of vectors, for example:
$$v_{1}=((0,0,0),(0,1,0),(0,0,1),(1,1,1))$$
$$v_{2}=((0,1,0),(1,1,1),(0,0,0),(0,0,1))$$
I want to find a way of verifying that both $v_{1}$ and $v_{2}$ ...
- 491
5
votes
2
answers
267
views
6
votes
7
answers
603
views
Dropping disordered numbers in a list
I have a list of numbers like
l1 = (1,2,3,4,8) and clearly, l1 is in order (next number is greater than previous number).
Well, ...
- 405
3
votes
4
answers
211
views
Build a region from an unsorted set of points (Imported from a .DXF file)
Please consider trying to download the following .dxf files :
DXF File - HEA
DXF File - UNP
DXF File - RRW
Context :
Every file contains a drawing of a particular type of steel profile used in civil ...
- 508
3
votes
1
answer
45
views
What is happening behind an evaluation of Sort with meaningless order-function?
If we try Sort[] with meaningless order-function like
Sort[{3, 2, 1}, True]
or,
...
- 359
-1
votes
1
answer
75
views
Finding the dimensions of the cylinder that can cover $n$ given smaller cylinders (based on empty space, not least materials)
Let $r_k$ and $h_k$ be, respectively, the radius and the height of the $k^\text{th}$ cylinder. We have $n$ cylinders.
Let $R$ and $H$ be, respectively, the radius and the height of the big that can ...
- 280
0
votes
1
answer
66
views
How to sort this two elements of a list?
Hi So I have the following list:
data = {{3.73324*10^10 + 147881. s + 1. s^2, 1}, {3.73324*10^10 + 357017. s + 1. s^2, 1}}
(this is a short example, in this case ...
1
vote
0
answers
28
views
How to sort a list of n-tuples by a given column, or by the norm? [closed]
I would like to sort a list of lists by the third column (third element in each row), or by the norm of each row, but Mathematica 13.1 ignores my syntax, i.e. returns the same unordered answer
...
- 1,642
1
vote
1
answer
44
views
Collect with rational powers
I need a function, which will collect terms next to the same rational power of a given variable. For the input
RCollect[3xy^(3/2)+2/y+zx/y-y/x+2*x^z y^(3/2),y]
the ...
- 95
1
vote
2
answers
309
views
Sorting 300K .h5 files
I have 300K .h5 files. I want to list them and plot the data with respect to a parameter. They must be sorted by name otherwise, the plot will be wrong because of time dependency. The name of the ...
- 349
1
vote
1
answer
94
views
Sorting by power
I want to sort this table by column "d" such that Mathematica should also take the exponential values into account. Can somebody help me here?
- 73
2
votes
2
answers
201
views
Sorting a List Based on a Given Order
Suppose I have the following input:
input={{1, 2, 3}, {-2, 4, 6}, {-1, 3, 6}}
How can I sort it according to this list:
...
- 2,411
6
votes
2
answers
227
views
Sorting a list by a single particular element in a specified order
I have a list of lists -- a list of sublists -- that I wish to sort in a specified order. The following function, sortBy2ndElement, sorts a list of lists (...
- 10.4k
3
votes
2
answers
113
views
Order elements of list according to predefined ordering [closed]
I have quite a lot of sublists of different length whose elements I would like to order according to a specific predefined ordering.
To be explicit: I am given a specific ordering of indices (i,j,k,l,...
- 91
1
vote
3
answers
116
views
Is it possible to prevent two functions from commuting?
I have an expression of the following type:
x f[a] g[b]
where x is a number but f[a] and <...
- 691
6
votes
1
answer
262
views
Sort the nested list by the sublist content; sublists of different lengths
I would like to write the function NewSort function that sorts a list of sorted sublists, basing first on the canonical ordering of subsequent sublist elements. In ...
- 95
3
votes
1
answer
78
views
Basic question Sort criteria
Can you explain the following codes? (output of codes)
I know that
there is the default ordering for any expression in Mathematica
and Sort uses the default ...
- 4,047
2
votes
1
answer
85
views
Cycle symmetric Sort for arguments of a function. Put trace in canonical order
I need a new Sort for the arguments of TR that maintains cyclicity, TR[a,b,c] = TR[b,c,a] = TR[c,a,b]
cyclicSort[TR[b,a,c]]
TR[a,c,b]
...
- 966
7
votes
1
answer
228
views
Ordering Arguments of Antisymmetric Functions in Cyclic Way
I have two functions ang and sqa, each of which take two arguments which must be distinct integers between 1 and 6. For instance I could have ang[2,1] or ...
- 137
3
votes
3
answers
76
views
Sort a list using a scoring list with Switch [duplicate]
I have a minimal working example (MWE) list called listToSort that is a list of string triplets:
...
- 10.4k
5
votes
1
answer
145
views
Fail to understand Ordering[], need to get the ranking of elements in a list
Ordering[{2, 1, 6, 4, 7, 10}]
gives me as a result, {2, 1, 4, 3, 5, 6}, which I understand, 10 is the 6th smallest element. However
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- 131
8
votes
2
answers
319
views
SortBy with a 2nd argument that specifies not to sort the list?
One can specify the second argument of SortBy not to sub-sort ties, i.e. cases that have identical values according to the main sorting function. ...
- 46.7k
0
votes
1
answer
52
views
Sorting a list by increasing order algorythm [closed]
Im new to loops on mathematica,was wondering how could I create a function to loop through a list which finds the index of the smallest value of that list, makes a sublist from index 1 to that ...
- 93
6
votes
3
answers
320
views
How to Partition List into sublists so that it orders down columns when placed into a Grid instead of across rows
Partitioning a List into sub-lists and placing them directly into a Grid orders sub-lists across rows. Is there an idiot-proof built-in function or a simple ...
- 2,407
1
vote
0
answers
36
views
How to create a Sort function that does not differentiate between String rule keys and Symbol rule keys
Im trying to Sort Rule-s according to Key-s (or names) but the normal ...
- 2,407
3
votes
3
answers
227
views
Sorting a list based only on a certain property of the first element of sublists
Suppose I have a list called roster. Each element in roster is a list containing two strings: (i) the species of animal and (ii) ...
- 10.4k
0
votes
1
answer
79
views
Sorting a dataset on multiple column
Following an answer provided by kglr in a previous post:
...
- 1,774
1
vote
2
answers
110
views
Sorting a symmetric matrix alphanumerically
NOT related to my related question! (Different problem source)
This time, I want to sort a symmetric matrix M, and it must stay symmetric (i.e. row and col sort is the same). WLOG the diagonal is 0 (...
- 1,001
1
vote
0
answers
134
views
SortBy the second element in the sublists
Is there a way to sort sublists in a list by the sublists' second element?
For example, if the list is:
...
- 465
3
votes
2
answers
435
views
How can I sort {S1, S15, S19, S2, ...}?
How can I sort this in order from small to large?
Simple Sort doesn't work here.
...
- 2,688
4
votes
4
answers
185
views
Creating a cycle with conditions
I would like to arrange a gift exchange between 5 people, Alice, Bob, Carl, Danny, and Ellen, and I would like the gifts to be passed in a randomly created cycle (B->C->A->D->E->B), for ...
- 792
4
votes
3
answers
325
views
Insert without extra brackets
I have a List1:
{{1, -1.1}, {2, -1}, {3, -0.9}, {4, 0}, {10, -0.4}}
and List2:
{{2, -0.6}, {3, -0.6}}
and I would like insert ...
- 1,753
0
votes
1
answer
52
views
4
votes
3
answers
354
views
How to replace the element in list of list by its ordering index
I have a list of list: res={{9, 1, 5}, {3, 6, 12}}
I want to change it to res={{5, 1, 3}, {2, 4, 6}}
by following their ordering ...
- 95
10
votes
7
answers
518
views
Collect terms with the same denominator
I have an expression
$$\frac{A}{x}+\frac{A_2}{x^2}-\frac{D_2}{x}+\frac{C_2}{x^2}++\frac{F_2}{x^3}+\frac{I_2}{x^2y}+\frac{U_2}{y^2x}+\frac{Z_3}{x^2y}+\frac{J_2}{y^2x}+\cdots$$
and I am looking for a ...
- 231
3
votes
4
answers
219
views
Finding relative ordering of two lists
Suppose you have two lists A and B which are related by a permutation, and have no repeated elements.
Is there a simple and ...
3
votes
2
answers
93
views
Parting a table by second column elements
I have 2 X m table with elements {{x1, y1}, {x2, y2}, .... {xi, yi}, .....{xm, ym}}. It is an experimental data, which can be seen in the attached picture. There is a significant noise and ...
- 1,185
6
votes
4
answers
651
views
Find min and max indices of highest and lowest elements in sorted list
I have a list of integers of the form
...
- 239
2
votes
4
answers
221
views
Counting number of points in fluctuating lines that fall within a circle
I have a list of points pts that fluctuate around some mean line. pts is pre-sorted by the projection of the points onto this ...
- 239
6
votes
1
answer
166
views
Fastest Way to Find nearest indices between two sorted lists
I have a sorted list of floats of length n and an n x n list of lists, where each nested ...
- 239