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Re: A question about thinking 'abstractly'....

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In article <4e2b2ba0$0$44211$4fafbaef@reader1.news.tin.it>,
io_x <a@b.c.invalid> wrote:
> 
> "blmblm@myrealbox.com" <blmblm.myrealbox@gmail.com> ha scritto nel messaggio
> news:990fq1F8n9U4@mid.individual.net...
> > In article <j092hi$iaf$1@dont-email.me>, BartC <bc@freeuk.com> wrote:
> > ====
> >
> > For x >= 0, the return value of sqrt(x) is a number y such that
> > y >= 0 and abs(y*y - x) <= $THRESHOLD_VALUE.
> >
> > ====
> >
> > If A references an array of size at least n, after execution of
> > sort(A, n), A[i-1] <= A[i] for all i in the range 1 <= i <= n-1.
> >
> > ====
> 
> it is all formal
> if you not replace the english words with simbols you not have
> a language ok

I have no idea what you mean here, sorry.  No offense meant [*], but
I often have trouble with your attempts at English.  Maybe someone
else can translate.  Or not.

[*] Since I'm unfortunately one of those native speakers who can't
claim fluency in any other language.  "Some knowledge" yes, but
fluency no.  So I'm not in a position to be critical.

I'm not doing much better with the text below but will attempt
a few comments:

> all is formal i.e. the good way of build right symbols from axioms;
> programming langages as math are one game build symbols from axioms
> that seems to have no pratical meaning :)
> they have their meaning as build of allowed set of symbols
> they not need other; in pratice we build one home 10000000000000000
> can be build
> 
> registers are real points that contain 32 bits unsigned numbers
> a,b,c,r, etc .
> One can sign them in a real[R] X axist

I'm not sure how well it works to think of register contents as
real numbers, given that the reals are uncountable and the set
of possible values for something with a finite number of bits is
not.  But maybe that's not what you meant anyway?

I wonder, though, whether you're describing some sort of variant
on a Turing machine??

> memory is a array of points in the y axist
> address 0..maxIndxMemory
> 
> than there is the time[here] that is represented from
> the formal way to met first instruction symbols
> 
> than there are operations of the set of registers
> +:R32bit x R32bits -> R32Bit
> etc
> code could be as a theorem
> theorem
> a=0|b=0|c=3|r=c+b => r=3
> 
> it is like in a debug window we see a=0|b=0|c=3|r=c+b
> than in the debug window we see r==3 is true
> 
> math can have goto for explain algo one meet in math too
> 
>    c=a+b|if c==3 goto v|c=9
> v:
> 
> where is the difference?
> 
> the difference is only with algo we not are sure 100%
> of the result even if we debug the code...

Another important difference might be that sometimes one can
formally prove the correctness of an algorithm, but in a way
that ignores some implementation issues such as the finiteness
of most computer representations of numbers.  (The example that
comes to mind involves binary search and how finding the middle
of the index range i1 .. i2 by computing (i1+i2)/2 fails if
the addition produces overflow.)

> because algo seem to be a little difficult
> 
> but algo are in math
> 
> with the teorems all seem easier if read the math book
> and understand it
> 
> at last i think that until now

-- 
B. L. Massingill
ObDisclaimer:  I don't speak for my employers; they return the favor.

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Thread

A question about thinking 'abstractly'.... Chad <cdalten@gmail.com> - 2011-07-19 12:20 -0700
  Re: A question about thinking 'abstractly'.... Ben Bacarisse <ben.usenet@bsb.me.uk> - 2011-07-19 21:26 +0100
  Re: A question about thinking 'abstractly'.... "Kleuskes & Moos" <kleuske@xs4all.nl> - 2011-07-19 14:02 -0700
  Re: A question about thinking 'abstractly'.... Ulisses Araujo Costa <ulissesmonhecosta@gmail.com> - 2011-07-20 02:23 -0700
    Re: A question about thinking 'abstractly'.... "Kleuskes & Moos" <kleuske@xs4all.nl> - 2011-07-20 03:46 -0700
      Re: A question about thinking 'abstractly'.... Ulisses Araújo Costa <ulissesmonhecosta@gmail.com> - 2011-07-20 09:50 -0700
  Re: A question about thinking 'abstractly'.... Rui Maciel <rui.maciel@gmail.com> - 2011-07-21 04:27 +0100
    Re: A question about thinking 'abstractly'.... "BartC" <bc@freeuk.com> - 2011-07-21 12:27 +0100
      Re: A question about thinking 'abstractly'.... blmblm@myrealbox.com <blmblm.myrealbox@gmail.com> - 2011-07-23 17:47 +0000
        Re: A question about thinking 'abstractly'.... "io_x" <a@b.c.invalid> - 2011-07-23 22:16 +0200
          Re: A question about thinking 'abstractly'.... blmblm@myrealbox.com <blmblm.myrealbox@gmail.com> - 2011-07-25 19:39 +0000
    Re: A question about thinking 'abstractly'.... Nick Keighley <nick_keighley_nospam@hotmail.com> - 2011-07-21 05:11 -0700
    Re: A question about thinking 'abstractly'.... August Karlstrom <fusionfile@gmail.com> - 2011-07-21 15:14 +0200
    Re: A question about thinking 'abstractly'.... Nick Keighley <nick_keighley_nospam@hotmail.com> - 2011-07-22 03:50 -0700
    Re: A question about thinking 'abstractly'.... Nick Keighley <nick_keighley_nospam@hotmail.com> - 2011-07-23 06:33 -0700
    Re: A question about thinking 'abstractly'.... Nick Keighley <nick_keighley_nospam@hotmail.com> - 2011-07-25 03:41 -0700
    Re: A question about thinking 'abstractly'.... Nick Keighley <nick_keighley_nospam@hotmail.com> - 2011-07-25 06:06 -0700
  Re: A question about thinking 'abstractly'.... Nick Keighley <nick_keighley_nospam@hotmail.com> - 2011-07-25 03:42 -0700
    Re: A question about thinking 'abstractly'.... Nick Keighley <nick_keighley_nospam@hotmail.com> - 2011-07-25 06:07 -0700
      Re: A question about thinking 'abstractly'.... Nick Keighley <nick_keighley_nospam@hotmail.com> - 2011-08-10 03:57 -0700

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