MatStash() use linked list of chunks

[Richard Katz]

Matt,

When we get together to work on the semi-Lag stuff we should make this 
interface clear.

Rich


On Dec 13, 2005, at 4:38 PM, Barry Smith wrote:

>
>   Rich,
>
>    Outline what you use/need in terms of an interface for that case.
> We can gather the cases to see what commonality comes out.
>
>    Barry
>
> BTW: I was joking about the "stinking ..."
>
>
> On Tue, 13 Dec 2005, Richard Katz wrote:
>
>> A PETSc linked-list object might also be useful in implementations of
>> characteristics-based advection schemes such as semi-Lagrangian 
>> advection.
>> Perhaps you could give it some sorting methods too?
>>
>> but then again, this is just "stinking computer science"...
>>
>> Rich
>>
>>
>> On Dec 13, 2005, at 1:22 PM, Richard Tran Mills wrote:
>>
>>> I agree with Matt's take on this.  Having a linked-list to be used
>>> throughout PETSc as appropriate could be quite useful.
>>>
>>> I am a fan of doubly-linked list implementations like the one 
>>> described at:
>>>
>>>   http://www.cs.utk.edu/~plank/plank/classes/cs360/360/notes/Dllists/
>>>
>>> (This is part of Jim Plank's libFDR library, which also includes a 
>>> nice
>>> red-black tree implementation.)
>>>
>>> Jim's Dllist stuff stores "Jvals" which are a union of all intrinsic 
>>> C data
>>> types -- that way you can stash whatever you want in a node of the 
>>> list.  I
>>> don't know if an approach that general is needed in PETSc or not, 
>>> but the
>>> flexibility is nice.
>>>
>>> --Richard
>>>
>>> Matthew Knepley wrote:
>>>
>>>>      If we are really going to do this, shouldn't we approach it as 
>>>> a
>>>> data structures problem? We need a certain structure, which here 
>>>> appears
>>>> to be "vector", or maybe "list". We make a general interface, and 
>>>> then
>>>> code up some implementation, like a linked list. Then we can use 
>>>> this
>>>> interface/impl other places in the code, like the LU part, rather 
>>>> than
>>>> rely on our old cut&paste strategy.
>>>>      Matt
>>
>>