Is it possible to make a vector of pair of pairs of two integers?or else can you suggest a way to create a structure where there is four attributes of each member and needs to sort based on the first one , in case of equality the second and so on..
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By using the IndependentSets module in SageMath, we can list all the independent sets of a graph. Suppose I have a bipartite graph on the Symmetric Group with partite sets consisting of even and odd permutations.
How do I enumerate and list out all those independent sets which consists of equal number of elements from even and odd permutations. What all methods and functions do I need to use. Is there some built in function for listing the type of a symmetric group element as even or odd.
My idea of pseudo-code idea would be:
G=BipartiteGraph()
I=IndependentSets(G)
for list in I:
for i in list:
if enumerate(type(list[i])=='even')==enumerate(type(list[i]=='odd'):
add list in list1
print(list1)
However, I encountered the error that list indices must be integers or slices and not permutation group elements. How do rectify this? Any hints?
How to express a conditions for two consecutive variable length relationships?
Consider this partial query
MATCH(t1:Type{myID: 1})-[r:relType]->(:Type)-[rels:relType*0..]-(t2:Type{myID:100})
WHERE r.attr1>10
Basically I am trying to saying that there could be one or more relations from t1 to t2. The first relation r should satisfy a given condition on its attribute.
If this is the only relation between the two nodes then it's ok.
It at least another relation exist I want to add another condition such as:
WHERE r.attr1>10 AND r_next.attr2> r_prev.attr2+r_prev.attr1
where r_next and r_prev are consecutive relations: ()-[r_prev]->()-[r_next]-(). Note that at the first step r_prev is the first relation r.
I know rels is a collection but I do not know how to express such a condition.
Consecutive comparison like this isn't easy at this time, and it can't currently be evaluated during expansion.
You can do some filtering on this after, but it will be ugly.
We'll make use of the APOC Procedures for apoc.coll.pairsMin(), which takes a collection and returns a list of adjacent pairs.
MATCH (t1:Type{myID: 1}), (t2:Type{myID:100})
MATCH (t1)-[r:relType]->(:Type)-[rels:relType*0..]-(t2)
WHERE r.attr1>10
WITH t1, t2, apoc.coll.pairsMin(rels) as pairs
WHERE all(pair in pairs WHERE pair[0].attr1 + pair[0].attr2 < pair[1].attr2)
RETURN t1, t2 //or whatever you want to return from this
I'm needing to subset a list which contains an array as well as a factor variable. Essentially if you imagine each component of the array is relative to a single individual which is then associated to a two factor variable (treatment).
list(array=array(rnorm(2,4,1),c(5,5,10)), treatment= rep(c(1,2),5))
Typically when sub-setting multiple components of the array from the first component of the list I would use something like
list$array[,,c(2,4,6)]
this would return the array components in location 2,4 and 6. However, for the factor component of the list this wouldn't work as subsetting is different, what you would need is this:
list$treatment[c(2,4,6)]
Need to subset a list with containing different classes (array and vector) by the same relative number.
You're treating your list of matrices as some kind of 3-dimensional object, but it's not.
Your list$matrices is of itself a list as well, which means you can index at as a list as well, it doesn't matter if it is a list of matrices, numerics, plot-objects, or whatever.
The data you provided as an example can just be indexed at one level, so list$matrices[c(2,4,6)] works fine.
And I don't really get your question about saving the indices in a numeric vector, what's to stop you from this code?
indices <- c(2,4,6)
mysubset <- list(list$matrices[indices], list$treatment[indices])
EDIT, adding new info for edited question:
I see you actually have an 3-D array now. Which is kind of weird, as there is no clear convention of what can be seen as "components". I mean, from your question I understand that list$array[,,n] refers to the n-th individual, but from a pure code-point of view there is no reason why something like list$array[n,,] couldn't refer to that.
Maybe you got the idea from other languages, but this is not really R-ish, your earlier example with a list of matrices made more sense to me. And I think the most logical would have been a data.frame with columns matrix and treatment (which is conceptually close to a list with a vector and a list of matrices, but it's clearer to others what you have).
But anyway, what is your desired output?
If it's just subsetting: with this structure, as there are no constraints on what could have been the content, you just have to tell R exactly what you want. There is no one operator that takes a subset of a vector and the 3rd index of an array at the same time. You're going to have to tell R that you want 3rd index to use for subsetting, and that you want to use the same index for subsetting a vector. Which is basically just the code you already have:
idx <- c(2,4,6)
output <- list(list$array[,,idx], list$treatment[idx])
The way that you use for subsetting multiple matrices actually gives an error since you are giving extra dimension although you already specify which sublist you are in. Hence in order to subset matrices for the given indices you can usemy_list[[1]][indices] or directly my_list$matrices[indices]. It is the same for the case treatement my_list[[2]][indices] or my_list$treatement[indices]
Consider the problem where you have a list which needs to be split into multiple lists (buckets) given a function given an element and returning the index of the destination list (bucket). The output of the operation is a list of lists.
What's the correct name for this operation?
You can also call it partition.
One name would be grouping: the Scala function that does this is groupBy (though it returns a Map from discriminator keys to Lists instead of the list of lists you're asking for).
If your list is ordered and the function in question splits into multiple buckets of roughly equal size (for some notion of size), then it could be called quantiling.
I have a problem whereby I have several discrete lists of ID's eg.
List (A) 1,2,3,4,5,7,8
List (B) 2,3,4,5
List (C) 4,2,8,9,1
etc...
I then have another collection of ID's...
For example: 1,2,4
I need to try and match one into each list. If I can perfectly match all ID's in my secondary collection (one collection ID matched with an ID from each list) then I get a true result....
I have found that it becomes complicated because if you simply iterate over the lists matching the first collection/list pair that you encounter it may result in you precluding a possible combination further on down the line hence returning a false negative result.
For example:
List (A) 1,2,3,4
List (B) 1,2,3,4
List (C) 3,4
Collection is: 3,1,2
The first ID from the collection (3) matches with an entry in list A, the second ID in the collection (1) matches an item in list B, however the final ID in the collection (2) DOESNT match any entry in list C however if you rearrange the order of the collection to be: 2,1,3 then a match is found.... Therefore I am looking for some form of logic for attempting a match on all possible combinations in an efficient manner(?)
To make it more complicated the ID's are actually GUID's so cant just be sorted in ascending order
I hope I have described this well enough to make it clear what I am attempting and with a bit of luck somebody will be able to tell me that what I need to do is very easy and I am missing something real simple!
I am forced to code this in VB6 but any methods or pseudo code would be great. The backend of this is SQL server so if a solution using TSQL was possible this would be even better as all of the ID's are held in tables already.
Many thanks in advance.
Jake, yep the lists and the collection both contain GUIDS. I used plain integers to simplify the problem a bit.
Once a list has been matched it cant be searched again, hence the ordering problem that I tried to explain. If you say that a list as 'matched' then no further attempts to match this will be performed. It is this very behaviour that can cause a false negative.
'Sending' the collection in in every possible combination of orders would work but would be a massive job .....
I feel I must be missing a really straightforward concept or solution here??!!
Thanks for your assistance so far.
I don't see a way around checking each GUID contained in the lists against each GUID in the collection. You would have to keep record of in which lists each GUID in the collection occurs.
To use your example of the Collection (3, 1, 2), 3 occurs in List A, B and C.
You will basically be left with this dataset.
3 (A, B, C)
1 (A, B)
2 (A, B)
Once you have distilled it down to this dataset you can determine whether there are any GUIDs with zero occurrences in the lists which would result in a negative.
I am not at all well versed in algorithms, but this is how I would proceed after that :
Start with the first set (A, B, C), and check how many times it occurs further on in the dataset. In this case no occurrences are found.
Moving on to the next set (A, B), if the number of occurrences of this set is found to be greater than the length of this set, i.e. more than two occurrences, would result in a negative. If the number of occurrences match the length exactly, as is the case here, the set (A, B) can be removed from any further consideration.
3 (C)
1 ()
2 ()
I guess you would continue to repeat the process until a negative is identified or all the occurrences have been excluded. There is probably a recognized algorithm for this sort of problem, but my knowledge is a bit lacking in that respect. :(