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In some scientific papers I see that authors provide what type of simulation tool and what type of computer was used for computation. For example:

The computations were performed using MATLAB in double precision on a VAX 11/780 computer, the unit roundoff $u=2^{-56}\approx1.39\times10^{-17}$.

From my understanding Matlab has double precision by default and we can change it. And using the round function we can specify roundoff. But what should I specify in the type of computer part? Is this one correct: on a Intel(R) Core(TM) i5-3470 CPU @ 3.20GHz computer?

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    $\begingroup$ Yes, this seems like a reasonable description of what your computer is. $\endgroup$ Commented Aug 21, 2021 at 3:15
  • $\begingroup$ RAM is also important, both that you have enough of it that you don't use swap for the computation and that it's not some old, slow RAM chip. $\endgroup$
    – Richard
    Commented Aug 22, 2021 at 15:24

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From my understanding Matlab has double precision by default and we can change it.

Sort of. You can force it to run computations in single-precision, but you need to be very careful or your variables will be silently promoted to double precision. You can also use variable precision arithmetic (vpa, I think it's in the symbolic toolbox), but it is a lot slower and many functions do not work properly with it. A much better description is that Matlab is a tool built to work with binary64 (double precision) floating point numbers, and using everything else would be a kludge.

And using the round function we can specify roundoff.

Uhm, no, not at all. round rounds one single number to a specified number of decimal digits (approximately, because internally all numbers are represented in base-2). All arithmetic is still performed with the standard roundoff for double precision.

But what should I specify in the type of computer part? Is this one correct: on a Intel(R) Core(TM) i5-3470 CPU @ 3.20GHz computer?

That sounds OK. You may want to specify also the Matlab version used. Many specify also the amount of RAM, but it is less clear if it serves a purpose or not in this context. If you are using Linux or Mac, you can get your processor's description with cat /proc/cpuinfo | grep "model name (note that there is one such line per virtual core, but they usually all coincide).

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