Testing MATLAB to the limits!

MATLAB users Hello!

I need to construct 6 billion pairs of some numbers and I would like to know if there is anything that I can do to increase the performance/speed/memory of MATLAB.

I use r2012a and r2009

Thanks in advance!

[Daniel Shub]

What exactly are you going to do with all this data? It is unlikely that you will have enough RAM to load it all into memory and then do anything with it. Even saving it to a file is going to be painful.

[Yash]

your Matlab will give out of memory error

Answer 1

[per isakson]

1. use 64bit Matlab
2. use uint8 if possible
3. install a lot of RAM
4. pre-allocate
5. use the function, PROFILE

    >> 6e9*2*8/1e9
    ans =
        96

[loukos]

what is:

6e9*2*8/1e9
  ans =
      96

[per isakson]

That is "6 billion" x "pairs" x "8bytes" converted to GB.

[Sebastian Holmqvist]

While the data would amount to a whopping 96 Gigabytes (using uint8), since computers are binary-based you have to represent data in Gibibytes (1024^3) if you wish to store them to disk.

6e9*2*8/1024^3 = 89.407 GiB data on disk. On top of that you can expect some file overhead data, which depends on your method of storing the data. When it comes to memory, you still need 96 GB.

[per isakson]

Not uint8, "8bytes" stands for double.

Answer 2

[Greg Heath]

help memory

doc memory

Pre-allocate space as much as possible.

Greg