Re: [uima] Type System Base Model v.4

From
Karin Verspoor <>
Date
2007-04-10T22:03:15+00:00
ID
Thread
Re: [uima] Type System Base Model v.4
Title: Re: [uima] Type System Base Model v.4

Thanks, Adam.

I hadn’t considered the question you raise, so I do appreciate it.

I’d be inclined to require the use of “real” Unicode character offsets for standardization purposes.

I think for Apache UIMA to be compliant, it would just need to accept/handle CASes with Unicode offsets, and whatever happens “under the hood” is not up to us, is it?

Karin

On 4/2/07 10:12 AM, "Adam Lally" <> wrote:

Karin, 

Overall looks good.  I have a comment about the TextAnnotation and TextRegionalReference definintion. 

There are some tricky details regarding a standard definition of beginChar, endChar.  What exactly do these values represent - Unicode character offsets?  Note that Apache UIMA does not use Unicode character offsets, but rather "UTF-16 code unit" offsets - that is, each element is a 16-bit value like a char in a Java String.  This has the advantage of allowing constant-time indexing (e.g. for getCoveredTex).   Unfortunately not all Unicode characters can be represented in 16 bits, so sometimes a single Unicode character is split across two 16 bit values.  Apache UIMA doesn't use true Unicode character offsets in that cases.  This is especially inconvenient for anyone using UTF-8 rather than UTF-16 (for example, Perl annotators).  

I'm not sure what the right answer it, but using "real" Unicode character offsets seems like it's a more appropriate use of the Unicode standard.  Then, for Apache UIMA to be compliant does it just need to accept XMI CASes with Unicode offsets and covert them to its own internal representation?  Or would the internal representation have to actually change (which would be ugly). 

Regards, 

  -Adam 

_____________________________

 Adam Lally

 Advisory Software Engineer 

 UIMA Framework Lead Developer

 IBM T.J. Watson Research Center

 Hawthorne, NY, 10532

 Tel: 914-784-7706,  T/L: 863-7706

  

Karin Verspoor <> 03/30/2007 01:50 PM 

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Subject

[uima] Type System Base Model v.4 

Please find attached the reviewed document outlining

changes/proposals/action plan for the Type System Base Model.

Comments welcome.

Karin

_______________________________________________________________

Karin Verspoor, Computational Linguist

Knowledge and Information Systems Science team

Computer, Computation & Statistics division

http://public.lanl.gov/verspoor

email:    Mail: Los Alamos National Laboratory

phone: 505-667-5086              PO Box 1663, MS B256

fax:   505-667-1126              Los Alamos, NM 87545

_______________________________________________________________

[attachment "TypeSystemBaseModel_v4.doc" deleted by Adam Lally/Watson/IBM] 

_______________________________________________________________

Karin Verspoor, Computational Linguist

Knowledge and Information Systems Science team

Computer, Computation & Statistics division

http://public.lanl.gov/verspoor

email:    Mail: Los Alamos National Laboratory

phone: 505-667-5086              PO Box 1663, MS B256

fax:   505-667-1126              Los Alamos, NM 87545

_______________________________________________________________