Questions on the sorting/ordering functions of Mathematica (Sort, SortBy, Ordering, etc.).
0
votes
1answer
36 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:
...
5
votes
3answers
145 views
Order list of monomials by degree (Pascal's Triangle)
Suppose I have the following list of monomials:
{1,x,x^2,y,y^2,x*y,x^2*y,x*y^2,x^2*y^2}
How could I manipulate it to get
...
4
votes
1answer
115 views
Sorting a matrix alphanumerically
Somewhat related to Sort matrix by columns and rows without changing them, but more general.
I'd like to sort a square matrix (a 3 by 3 in my case, but surely the general solution will treat any), ...
7
votes
1answer
76 views
Ordering function with recognition of duplicates
Fairly often I have a need to get the Ordering of an expression but with recognition of duplicates. For example:
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7
votes
3answers
163 views
Retaining and reusing a one-to-one mapping from a sort
Imagine I sort the elements of an array $Q$ by some means. Perhaps I sort strictly by the elements in the first column, perhaps I use SortBy[...] to sequentially sort by the elements in successive ...
0
votes
0answers
83 views
How can I sort the elements in a 3-dimensional table? [closed]
I'm doing a calculation where I need to sort the elements in a 3-dimensional table (because I have 3 running indexes), but I'd like to treat all of it as a 1-dimensional object and sort them by ...
8
votes
1answer
237 views
How can I collect data for visualization of quick sort?
I know how to implement quick sort in Mathematica. But I don't know how to get the temp data for visualization, because I used recursion. I want the effect like this.
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2
votes
1answer
90 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 ...
9
votes
5answers
328 views
Sort date list in format DD/MM/YYYY
I have a list of dates (ranging from 2007 to 2012) in the DD/MM/YYYY format and I need to sort this list.
My problem is, when I simply use Sort[] I get:
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8
votes
1answer
177 views
Sorting function for non commuting bosons
I am trying to write a sorting function which will sort expressions involving products of bosonic objects which do not commute. For example, I can have objects like $a,\ a^\dagger,\ b,\ b^\dagger$ ...
2
votes
2answers
139 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 ...
4
votes
6answers
185 views
Sorting Matrix elements
I have matrix in as shown, consisting of real numbers and 0. How can I sort it to become out as shown?
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1
vote
1answer
94 views
4
votes
1answer
145 views
Why can't I remove Orderless from Plus?
I am making some random algebra equations, and I want to have the ordering be random too, such that if my random equation generator makes x+1, the output stays ...
4
votes
2answers
99 views
Sorting list with variable
I want to sort (or sortby) the list. List contains uninitialized variable m and I can assume that m is a Natural number that is much larger then any constant.
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9
votes
1answer
98 views
Ranking Function Allowing for Ties
I have a list that I need to be able to assign ranks to individual elements in, giving it a number related to its position if the list were to be sorted, allowing for ties. For example, ...
4
votes
4answers
186 views
How to pick out the element in a list of lists which satisfies a particular condition?
I have got a list:
...
6
votes
2answers
204 views
Merging different size, different order table
I'm a beginner in Mathematica, so this may be a simple request. I have generated some columns of names and data. I want to merge them into a single list of names, with a column for each attribute.
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16
votes
4answers
355 views
Sort strings by natural ordering
Is there an easy way to sort strings according to their natural ordering?
For example a list of file names
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3
votes
2answers
160 views
18
votes
11answers
644 views
Generating an ordered list of pairs of elements from ordered lists
I have a pair of ordered lists. I want to generate a new ordered list (using the same ordering) of length n by applying a binary operator to pairs of elements, one from each list, along with the index ...
11
votes
2answers
319 views
Sorting a list with secondary criterion
Is there an easy way to sort a list on multiple levels of criteria?
By this I mean, first the list should be sorted according by criteria A (the same as using the usual sort function, ...
14
votes
5answers
369 views
How do I reassign canonical ordering of symbols?
I have a big polynomial that evaluates to:
$$A^2 e^2 \phi ^- \phi ^++A e \phi ^- \phi ^+ c_{2 w}
g_Z+\frac{1}{2} A e g h W^- \phi ^+ +\ll13\gg,$$
which is supposed to represent some terms in the ...
16
votes
4answers
534 views
Sort lists according to the order of another
I have three parallel lists (i.e. the elements in position i of each list are related). I want to sort the first list using the function Sort and make the same changes to the other lists so that I ...
4
votes
1answer
114 views
Sorting a list and finding an array of indices that sorts the list
How can I sort a list and also get a list of indices that sort this list?
For example:
primary list is a
a={1,4,6,7,0,2};
sorted list is b
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9
votes
1answer
133 views
How to pass composite function list to SortBy?
In order to sort alphanumeric-as-string data of the form {"T3", "T14", "T1", "E2"}, so that "T14" comes after ...
12
votes
2answers
772 views
Simple algorithm to find cycles in edge list
I have the edge list of an undirected graph which consists of disjoint "cycles" only. Example:
{{1, 2}, {2, 3}, {3, 4}, {4, 1}, {5, 6}, {6, 7}, {7, 5}}
Each ...
13
votes
3answers
683 views
Sort per column
I have some data:
data={{"a", 1, 1}, {"a", 1, 2}, {"a", 1, 3},
{"c", 2, 1}, {"b", 2, 2}, {"b", 2, 3},
{"c", 3, 1}, {"a", 3, 2}, {"a", 3, 3}}
When I ...
15
votes
2answers
358 views
Ordering problem
Let's look at the following example.
Ordering[{0, 20 Sqrt[5], 40 Sqrt[5], 20 Sqrt[5], 20 Sqrt[10]} // N]
gives the right answer
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7
votes
5answers
756 views
How to find rows that have maximum value?
Suppose if I have following list
{
{10,b,30},
{100,a,40},
{1000,b,10},
{1000,b,70},
{100,b,20},
{10,b,70}
}
How to find rows that have max value in ...
12
votes
4answers
279 views
How can we implement “Sleep Sort”?
Inspired by Implement Sleep Sort:
Sleep Sort is an integer sorting algorithm I found on the Internet. It opens an output stream, and for each input numbers in parallel, delay for the number ...
7
votes
2answers
178 views
How to generate Intervals from a given list?
If I have a list
list={3,7,4,5,1}
how to get the List of Intervals /Ranges
result = {{1,3},{3,4},{4,5},{5,7}}
