POV-Ray : Newsgroups : povray.advanced-users : Numerical Precision : Re: Numerical Precision Server Time
4 Oct 2024 19:20:44 EDT (-0400)
  Re: Numerical Precision  
From: Penelope20k
Date: 12 Sep 2007 04:36:34
Message: <46e7a512$1@news.povray.org>
an alternative method with modulo exist


#macro Want_decimal_of (  VarA , VarB , Nth)

#declare index=0;
#declare A=VarA;
#declare BASE=VarB;

#while(index<Nth)
#declare EUCLIDIANREST=mod(A,BASE);
#declare NTH_UNIT=(A-(BASE*EUCLIDIANREST) ) / BASE ;    // or
NTH_UNIT=int(A,BASE) ;  its the same



// REASSIGN FOR LOOP
#declare A=10*EUCLIDIANREST;
#declare index=index+1;
#end

// SORT THE RESULT UNDER STRING
 #debug str(NTH_UNIT,0,0)


#end










46e79def@news.povray.org...
> well need to calculate A/B
>
> well the units are:                         The rest of
> C0 = int (A/B)           ....................  R0 = A - C0 * B
>
> the first decimal is
>
> C1 = int ( (A - B * C0 ) *10 / B )   .........  C1 = int ( R0*10 / B)
> .............  R1 = R0*10 - C1*B
>
> C2 = int ( R1 * 10 /  B )
>
>
> Cn= int ( 10 * R(n-1) / B) .................... Rn = 10*R(n-1) - Cn*B
>
>
>
>
> Exemple: 7 / 11
>
> C0 = 0    R0 = 7
> C1 = int (70/11)   = 6           R1= 70-6*11 = 4
> C2 = int (40/11) =  3            R2 = 7
> C3 = 70/11 = 6                 R3 = 4
> C4 = 40/11 = 3                R4 = 7
>
> etc ...  with a loop willbe easy
>
>
>
>
> so 7 / 11   =   0.6309
>
>
>
>
> hope this will help you ....
>
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>

> web.46e41787bca8f08494e61a50@news.povray.org...
> > Does anybody know of a way, short of modifying the sourcecode, to
increase
> > the numerical precision that pov ray uses.
> >
> > For example say I need to calculate 1/3 to the 100th decimal place. I
> > believe it goes upto maybe the 8th or sixteenth place?
> >
> > Is there some ini option that can do this?
> >
> > What about declaring the value as you want it.
> > i.e. instead of writing
> > #declcare my_var = 1/3;
> >
> > declare it as
> > #declare my_var = 0.333333333333333333333333333333333333333333333333333;
> >
> > Would this do anything or would it truncate after a certain decimal
spot?
> >
> >
>
>


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