[cl-store-devel] store size of float in cl-store

kishor saitwal kishor_saitwal at yahoo.com
Fri Jan 15 20:08:23 UTC 2010


Hi there,

I was trying to figure out why the size of the stored file for any
float matrix is many times more than what it should be and hence
started looking into the actual package.

I realized that the integers take 8 bytes per integer as expected.
However, due to the splitting of the float into significand, exponent,
sign, etc. and saving those parts separately, one float value takes 51
bytes of memory to save. Is there any way to assign 8 bytes per float
in this package so that the size of the saved Matlisp matrices will not
be more than expected for such real values?

Within our save and restore mechanism, we need to save matrices that
would easily contain more than 1e6 floating point numbers and the
current mechanism makes the size of the saved sets large enough to be
concerned about the overall save and restore mechanism. We would
certainly like to find a way to save these big matrices in such a way
that the size is within 8 bytes per float.

Is there any way we can achieve this within the package without making
any changes? If not, can anybody recommend changes to the package in
order to achieve it? 

In general, I thought that it may be a good resource optimization if
the original package would have an option to assign maximum 8 bytes to
each float, if the user chooses to.

Any suggestions would be appreciated.

Thanks,
Kishor

-- 
Kishor Saitwal, PhD
Computer Vision Scientist
Behavioral Recognition Systems, Inc.
2100 West Loop South, 9th Floor
Houston, TX 77027
Voice: (713) 590-5160



      
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