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From: "meng long" <menglong6518@yeah.net>
Newsgroups: comp.soft-sys.matlab
Subject: Re: HDF5 Hight Level API
Date: Mon, 22 Jun 2009 18:17:01 +0000 (UTC)
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"meng long" <menglong6518@yeah.net> wrote in message <gubrmt$g57$1@fred.mathworks.com>...
> I want to know when "HDF5 Hight Level API"  is available in Matlab.

Dear Sir:

Thanks, I am glad to meet you for discussing HDF5 in deep case.

My table, for example, includes many columns "dOpnP,dClsP,dHgtP,dLowP,dVol,dMny" etc. which is used in financial-time-series application. For this practical application, many
different-type tables are dealt with. 

H5TB as HDF5 hight level API, is somewhat  a good case for my tables, except that I
cannot add attributes to the H5TB tables, inputs as 'Start, NRecords' in HDF5 hight level functions are difficult to used in financial-time-series application.

I have try to code a 'H5TB'  in matlab completely by using Matlab_Low_Level_Fuctions for HDF5, but 'my successful codes' is so slowly in reading data from the tables. For example, reading some data from 300 tables (100k each table) consumes 7-8 seconds, which is 5-6 times than loading 300 mat files storaged same data. The main seconds is consumed in communicating with hdf5lib2, in calling mex functions, etc.. In a word,  The main seconds is consumed in communicating with HDF5.

As a conclusion, it is not practical to construct a complex table_system by using Matlab_Low_Level_Fuctions for HDF5.

I have also try to code a complex table_system by using Matlab_Hight_Level_Fuctions for HDF5, but I give up, since hdf5write and hdf5read can be used in a simple application only, and is not flexible to a complex application.

I have try to code a complex table_system By SQL in matlab. Although, matlab is able to communicate with SQL (i.e, MS SQL)&#12290; However, the communication has a low
effective. I give up the slection. Now, I work up on the mat files. 

I hope that I work up on a Matlab_H5TB having same effective as mat files in recent future.

your friend
menglong