So^' sie^u phu+'c

[Hong Lam Vu <vuh000@goofy.zdv.Uni-Mainz.de>]

Hi folks,

Hu? le^'u tui di ho.c thi` do^'t nha^'t lo+'p ve6` toa'n, thi DH thi`
suy't ro+'t ddi ta^y chi? vi` ddie^?m toa'n, dda~ kho^ng bie^'t gi` ve^`
to'an la.i cu+' thi'ch no'i chuye^.n so^' ma'. Nha^n ba'c Paul raise vu.
so^' a^m so^' duo=ng le^n, tui intuitively nho+' co' la^`n ddo.c dda6u
ddo' ve^` so^' sie^u phu+'c cu?a o^ng Hamilton co' da.ng a + bi + cj + dk,
trong ddo' i^2=j^2=k^2= -1,
ij=-ji, ik=-ki, jk=-kj.

Ca'c ba'c hu? toa'n (ba'c Zu~ng, etc.) va` hu? ly' (ba'c So+n, ba'c
Tie^'n, etc.) la`m o+n cho bie^'t u+'ng du.ng cu?a so^' sie^u phu+'c
na`y vo+'i, ma` so^' sie^u phu+'c na`y ta ne^n hie^?u la` the^' na`o ho+?
ca'c ba'c?? Nghe no'i co' lie^n quan dde^'n spin.

Thanks in advance.
La^m.

On Mon, 10 Mar 1997, Paul Pham wrote:

> 
> sorry, need helps on another topic: representation of
> floating point in Digital computer ..
> 
> assume real-number is represented as 32-bits as follows:
> 
>    -------------------------------------------------
>       fraction                       ! exponent
>    -------------------------------------------------
>          24 bits for fraction         8 bits for exponent
> 
> the 1st bits of fraction and exponent is sign bit
> 
> the floating point must be normalized ;ie that the first bit and second
> bit in the fraction must be of opposite sign. for example
> 
> positive number   0 1 .......
> negative number   1 0 .......
> 
> so a real number is computed as  +- a * (2 ** b)
>    where  0.5  <=  abs(a) <= 1.0  (abs = absolute value)
>    and    -128 <= b <= 127
> 
> question: given a real number, need an alogorithm to convert it
>           into the above machine reprensentation.
> PDP
> 
> 
> hi all,
> 
> assume: negative integer is represented in digital computer
>         as 2 complement and assume 4 bits computer
> 
>  so  -3 looks like:  1101 
>              and     1101 = 13 as a positive number (forget the sign bit)
>                      13 = 16 - 3
> 
> so in general if we have n-bits computer, a negative integer number
> b in 2 complement is 2**n + b (in postive representation).
> 
> the above statement is intuitively true.
> Comment anyone ???.
> 
> PDP
> 
> 
> 
> 
> 
> 
>