Re: help : how to load only a part of a matrix in octave

[Francesco Potortì]

>
>Am 05.06.2012 12:35, schrieb Francesco Potortì:
>>> Am 04.06.2012 16:49, schrieb marco atzeri:
>>>> On 6/4/2012 4:00 PM, tharaka weheragoda wrote:
>>>>> I think fopen also load the huge matrix into memory.What i need is to
>>>>> load only a small part because i have only small memory.
>>>> cut the matrix in slices before feeding it to octave
>>>>
>>>> there are plenty of tools for that job
>>>>
>>>> Regards
>>>> Marco
>>> I think that is the only solution at all, I remember there was or is
>>> still a limitation in octave that limits the file pointer to 2GB.
>> This is not a problem if you read the file in slices using fseek and fread.
>>
>This is really useful to know, thanks.

To be more specific: as far as the file pointer is concerned, as far as
I know, the 2^31 limitation depends on the operating system libraries,
and I think that it is a thing of the past on all systems.

As far as the size of the matrix, the limitation of 2^31 is not on data:
it is on the index.  You can address any number of arrays, each with up
to 2^31 elements with the 32-bit version.  This was the status of Octave
in 2009, at least, and I guess it has not changed.

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