Hi Stefan,

How fast is the current weighted matroid intersection algorithm? It seems 
to be the naive augmentation one.

Also, I'm thinking about solving the following problems in the proposal.

1. Connectivity: fast algorithms for k-connectivity.
     - 3-connectivity algorithm by Bixby and Cunningham
     - k-connectivity using matroid intersection.
     - track down the faster 4-connectivity algorithm in Rajan's PhD thesis 
and see if it's reasonable to implement. [Rajan 1987]
2. Matroid intersection:
     - Implement the $O(n^{3/2}m)$ time algorithm for matroid intersection. 
$m$ is the groundset size, $n$ is the size of maximum common independent 
set. [Cunningham 1986]
     - fast weighted matroid intersection. (this can be ignored if the 
current one is already as fast) [Schrijver 2003, chapter 41]
     - Some applications based on matroid intersection: matroid partition 
algorithm, matroid union oracle.

I wonder if this is too little to do for the summer. 

On Friday, March 13, 2015 at 1:09:05 PM UTC-5, Chao Xu wrote:
>
> Hi Stefan,
>
> Thanks for the reply. I know the definitions for many matroid concepts and 
> its applications. 
> For example, I have no problem reading the chapter on matroid in 
> Schrijver's book.
> I don't have background with the deeper theories.
>
> On Monday, March 9, 2015 at 11:35:09 PM UTC-5, Stefan van Zwam wrote:
>>
>> Hi Chao,
>>
>> The state of the art in 3-connectivity algorithms is a 1979 book chapter 
>> by Bixby and Cunningham, see 
>> http://www.ams.org/mathscinet-getitem?mr=538038 (you'll have to dig it 
>> up from a library, most likely). For matroid union and intersection, 
>> Schrijver's 3-volume Combinatorial Optimization is a good reference.
>>
>> How much do you know about matroids?
>>
>> Cheers,
>>
>> Stefan van Zwam.
>>
>> On Tuesday, March 3, 2015 at 2:39:49 PM UTC-6, Chao Xu wrote:
>>>
>>> Hi all!
>>>
>>> I'm Chao Xu, a computer science PhD student at UIUC. 
>>> - I had experience with Sage a few years ago during an REU, and I 
>>> sometimes dub in python. 
>>> - I have lot of experience implementing algorithms(although it's in 
>>> Java).
>>> - I'm interested in combinatorial optimization, and believe implementing 
>>> some algorithms for matroid seems to be a good introduction to this field.
>>>
>>> Any papers could bring me up to speed with the current state of art? So 
>>> I might get a feeling of what is feasible.
>>>
>>> Best,
>>> Chao
>>>
>>

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