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From: NZTideMan <mulgor@gmail.com>
Newsgroups: comp.soft-sys.matlab
Subject: Re: Incoerences in MATLAB
Date: Thu, 11 Dec 2008 16:00:33 -0800 (PST)
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On Dec 12, 12:37=A0pm, "Trouble Finders Costa"
<valencada...@hotmail.com> wrote:
> I have discovered some incoerences and troubles in some commands of MATLA=
B. These problems caused me headaches by the time I have faced them for the=
 first time, because of the loss of several minutes in work until the perce=
ption of the problem.
>
> One of this problems, an incoerence, is: try if [125000:125000:10/0.00001=
] and [125000:125000:1000000] are vectors of the same dimension when genera=
ted in MATLAB.
>
> Another problem, a trouble, has to do with the question of numerical prec=
ision. Try the following commands:
> time =3D 0; time_increment =3D 0.01; n =3D (a number of your choice);
> for i =3D 1:n
> =A0 =A0 time =3D time =A0+ time_increment;
> end
>
> You will notice that, for large values of "n", some decimal numbers will =
appear after the second one. This shouldn't happen. I have observed this pr=
oblem for values of "time_increment" less than 0.1
>
> Thank you for your attention.
>
> Dante Valen?a.

What do you mean by "incoerence"?  You've written it 3 times, so it
cannot be a spelling mistake, but it is not an English word.  I
suspect it is a malapropism, but I'm not sure which word you're
getting at.
"incoherence", means a nonsense, but the fact that 10/0.00001 is not
the same as 1000000 in floating point arithmetic is not a nonsense.
The principle is well known and has been commented on many times in
this forum.

That these matters cause you headaches is a shame, but perhaps they
would cause you less concern if you learned from your mistakes and in
future refrained from trying to use floating point numbers as if they
were integers.