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1
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1answer
42 views
4
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2answers
229 views

Elegant way to partition list to be faster than `ParallelTable` (using `ParallelSubmit`), or some alternative?

Suppose you have a function fun[x_] := (Pause[.05*x]; x^2); of which you know that its evaluation time increases with its argument - in this case obviously ...
9
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3answers
324 views

GatherBy/SplitBy and Sort a list

So let's say I want to group a list of points based on their distance from the origin. I would do something like: ...
5
votes
2answers
157 views

How to make pairs of Young diagrams appear?

I have the following Young diagrams {{{0}, {2}}, {{0}, {1, 1}}, {{1}, {1}}, {{2}, {0}}, {{1, 1}, {0}}} where you can interpret each pair as following: For ...
0
votes
1answer
53 views

Timing and memory use is critical:fast partitioning of binary sparse array

I do experiments were I measure a signal, and I need to know at what time points it is above a threshold. If at a given time point, the signal is above the threshold, then a '1' gets put into the ...
3
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3answers
132 views
4
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1answer
210 views

Random Partitions

I want to write a function RandomPartition to partition a vector of length n into p partitions of varying (random) lengths. For example with ...
1
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2answers
67 views

Add elements to the maximum values of a list

Hi i have a list of n elements and i want to know the 30 maxim values of list without changing his order. And suppose that i have a second list with n elements and i want to add this elements to the ...
24
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1answer
708 views

Efficient lazy weak compositions

In Mathematica all weak k-compositions of integer n can be generated using permutations of integer partitions: ...
7
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3answers
214 views

generating integer partitions

Mathematica can generate integer partitions of an integer $N$. For example, IntegerPartitions[4] quickly gives ...
14
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2answers
157 views

How to partition a 2-D array properly?

Given that I have the following array lst = Array[Subscript[P, #1, #2] &, {5, 5}, {0, 0}] $ \left( \begin{array}{ccccc} P_{0,0} & P_{0,1} & P_{0,2} &...
2
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1answer
118 views

Need Help Writing code to find Capparelli Partitions

I am trying to add multiple criterion to IntegerPartitions[n] so that it sorts only partitions that fit the criterion. It creates a list of list of numbers in ...
17
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3answers
473 views

Improving speed of code computing number of nonrepeating partitions

I need to answer the following for a number of parameters: How many ways can the integer $k$ be written as a sum of $n$ different integers ranging from $1$ to $m$? My initial attempt was the ...
6
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0answers
78 views

Fast Partition of list at depth 2

I am looking to partition a list up at a certain depth level. Following code should demonstrate what I mean: ...
11
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5answers
549 views

Find all the possible ways of partitioning a list into a set of pairs of element

I have a list {x1,...,xN} where N is even, and I need to find all the possible ways to split it into pairs of elements, e.g. the ...
8
votes
4answers
168 views

Cluster numbers into n partitions so that each partitions sum is closest to total/n

For example having data data = {16, 4, 17, 10, 15, 4, 4, 6, 7, 14, 9, 17, 27, 6, 1, 9, 0, 12, 20, 8, 0, 3, 4, 0, 3, 4} I want to cluster them int 4 partitions <...
1
vote
3answers
154 views

Partitioning List Into Sublists of Length 2 With The Pairing Being Random

I've done a bit of Googling with hopes of finding an answer, but to no avail. I'm looking for a way that I can have Mathematica take the elements of a list, say ...
2
votes
1answer
116 views
1
vote
1answer
94 views

Integer partitions and dice result probabilities

This is a Project Euler question, so no spoilers :] I was going to try to solve it by first finding how many ways a certain sum can be acquired from a number of dice using ...
9
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2answers
217 views

Checking if one partition is a subpartition of another

Say I've got two partitions of a list (not necessarily containing numbers, and not necessarily distinct), and I want to check that one is a subpartition of the other. Let's look at some examples: <...
2
votes
4answers
364 views

Express integer as a sum of specific integers from a set, using each no more than once

I know there's a way to find partitions of an integer as a sum like: IntegerPartitions[12,All,{1,4,7}] which returns ...
1
vote
1answer
96 views

Is there a way to split a list (or number) into a specific number of parts?

I know there's a way to split a list into parts of a specific length, and I know there's a way to get all possible partitions of an integer. But I was wondering if there's a way to partition a list ...
4
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2answers
279 views

Partition a range of integers into triples

Some time ago, I was asked to look at a simple to formulate puzzle. Consider the list of numbers {1,2, ..., 33}. Try to split this list in 11 triples, such that in ...
15
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3answers
280 views

Partitioning with constraints on subsets

Given the following data: constraints = {{11, 2}, {11, 3}, {11, 4}, {11, 6}, {11, 9}, {1, 6}, {5, 6}, {2, 5}}; weights = {3, 7, 3, 2, 4, 2, 2, 2, 3, 2, 1}; I ...
4
votes
4answers
368 views

Partition list into a given number of sub-lists

I'm having quite a hard time with the following. I would like to partition a list into a list of sub-lists, in such a way that the number n of sub-lists is fixed. ...
2
votes
2answers
163 views

Speeding up the generation of all k-edge-coloring of a graph

A $k$-edge-coloring of a graph $G=(V,E)$ is a function from $E$ to $\{1,\ldots,k\}$, so in other words every edge of $G$ receives one of the $k$ colors available. (In particular, note that we are not ...
4
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2answers
214 views

Looping through a list partition

I got the following list and I would like to loop and partition this list in the following way. ...
3
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2answers
131 views

Partition a list dependent on consecutive list values

I have a list of 2D points which I partition every time the distance between consecutive list elements is bigger than a certain threshold. In a second step I select all the lists that start within a ...
1
vote
2answers
112 views

Make a partition with a rule [duplicate]

I wrote this line of code : {{1, 1, 1}, {1, 1}} /. ((x___ /; Length[x] > 2) -> Partition[x, 2, 1]) generates this error : Partition::pdep: Depth 1 ...
2
votes
1answer
85 views

Mathematica 8: EdgeList and CommunityStructureAssignment shadowing problem

I'm facing some issues when trying to use the CommunityStructureAssignment function from the GraphUtilities package in Mathematica 8. I'd like to output a ...
4
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4answers
352 views

Splitting a string into substrings of length 1 and 2

There is already a thread on how to split a string into equal sized chunks. I'm wanting to split a string into sets of substrings of length 1 and 2. For example, if I have the string "123456", my list ...
5
votes
1answer
254 views

Partitioning an image based on features

I have an image that has various characters hand drawn in it, like numbers and letters. I'm trying to partition each character into it's own image so I can run it through ...
2
votes
1answer
289 views

Using IntegerPartitions for distinct integers

What I would like to do is to find a way to test how many ways m distinct integers from the set {1,..., n} where ...
2
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3answers
272 views
1
vote
1answer
182 views

Partitioning a numerical integral: need to integrate spectra

I am trying to integrate a spectrum I obtained from a fourier transform infrared spectroscopy experiment, in order to determine the global warming potential of green house gases. In order to do this, ...
0
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2answers
96 views

Display Part Of or Summarize Other Notebooks

How might I display parts of(or basically summarizing) one Notebook from parts of several other Notebooks? This isn't a strict question question but more of a general/wiki question of how to organize ...
4
votes
3answers
241 views

Variable partitioning of the data in the form of “list of lists”

I am looking for a way for variable partitioning of the data in the form of a "list of lists" for interpolating the imported data from excel. The data looks like: ...
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8answers
1k views

Finding the midpoints of an ordered list of numbers

Suppose that I have an ordered list of numbers. The numbers in the list may be evenly spaced, but they may not be. Here are two examples, list1 and ...
15
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6answers
518 views

Partitioning an integer into $k$ equal parts

Say I have an integer $M$. Is there a one-line command to create a partition of $M$ into $k$ integers s.t. the difference between any two integers is as small as possible? For example, with $M = ...
4
votes
1answer
203 views

Finding the largest integer that cannot be partitioned in a certain way

I want to use Mathematica to solve the problem: Find the maximum $k$ such that $6x+9y+20z=k$ does not have a non-negative solution. I tried FrobeniusSolve. ...
5
votes
2answers
324 views

Partition a set into $k$ non-empty subsets

The Stirling number of the second kind is the number of ways to partition a set of $n$ objects into $k$ non-empty subsets. In Mathematica, this is implemented as ...
3
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1answer
296 views

Integer partitions in all orderings

I want to partition an integer into $k$ integers all possible orderings. This can be done in the following way ...
3
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3answers
601 views

Generating pairs of additive and multiplicative factors for integers

Given an integer $n$, I want to get two lists: a) the set of pairs of the divsors $a,b$ into exactly two factors $n=a\cdot b$, b) the set of pairs $a,b$ of two summands $n=a+b$. The code I ...