Re: Octave takes forever to load

[Nicholas Jankowski]

On Fri, May 31, 2013 at 11:34 AM, Ether Jones <address@hidden> wrote:

Jordi Gutiérrez Hermoso wrote:

> If your file is that small, I assume all of your numbers are single digits?

Most of the numbers are 0.  The rest are single or double-digit positive integers.

> Also, without a header the current algorithm parses the file twice,
> once to get the size of the matrix, and again to actually read the data in.

Even so, cut the 90 seconds in half and you get 45 seconds.
That's *way* longer than I would expect.
Is this a known bug in Octave, or am I doing something wrong?

> I also suspect all of this is completely unrelated to your actual problem...

I agree.

> ... it probably has to do with the peculiarities of Windows IO
> C++ libraries, which I've encountered before.

Is there a workaround for this?

> A matrix that size here in the free world loads in 4 seconds with a header
> and in 11 without a header.

Are you saying that you have a binary distro of Octave for 32-bit XP Pro
that loads a 2500x2500 12MB matrix in 4 seconds?

he's referring to a non-Windows operating system. question: have you tried both the MinGW and MS Visual Studio versions of Octave? since his linux(?) version loads it faster, then I would assume the basic algorithm in the code is not flawed, and the problem doesn't arise until compilation (hence his Windows libraries root cause suggestion).  Perhaps one windows complied version has a problem the other doesn't, which would be worth identifying.

nickj