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Calculate/Interpolate size of y in x^y = z when you do know "number of digits z" and base x?

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  Calculate/Interpolate size of y in  x^y = z  when you do know "number of  digits z" and  base  x? jonas.thornvall@gmail.com - 2015-05-11 04:22 -0700
    Re: Calculate/Interpolate size of y in  x^y = z  when you do know "number of  digits z" and  base  x? jonas.thornvall@gmail.com - 2015-05-11 04:28 -0700
      Re: Calculate/Interpolate size of y in  x^y = z  when you do know "number of  digits z" and  base  x? jonas.thornvall@gmail.com - 2015-05-11 05:47 -0700
        Re: Calculate/Interpolate size of y in  x^y = z  when you do know "number of  digits z" and  base  x? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2015-05-11 13:56 +0100
          Re: Calculate/Interpolate size of y in  x^y = z  when you do know "number of  digits z" and  base  x? jonas.thornvall@gmail.com - 2015-05-11 06:12 -0700
            Re: Calculate/Interpolate size of y in  x^y = z  when you do know "number of  digits z" and  base  x? jonas.thornvall@gmail.com - 2015-05-11 06:19 -0700
            Re: Calculate/Interpolate size of y in  x^y = z  when you do know "number of  digits z" and  base  x? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2015-05-11 21:49 +0100
    Re: Calculate/Interpolate size of y in  x^y = z  when you do know "number of  digits z" and  base  x? "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2015-05-11 15:19 +0200
      Re: Calculate/Interpolate size of y in  x^y = z  when you do know "number of  digits z" and  base  x? jonas.thornvall@gmail.com - 2015-05-11 06:25 -0700
      Re: Calculate/Interpolate size of y in  x^y = z  when you do know "number of  digits z" and  base  x? jonas.thornvall@gmail.com - 2015-05-11 06:30 -0700
        Re: Calculate/Interpolate size of y in  x^y = z  when you do know "number of  digits z" and  base  x? "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2015-05-11 18:18 +0200
          Re: Calculate/Interpolate size of y in  x^y = z  when you do know "number of  digits z" and  base  x? jonas.thornvall@gmail.com - 2015-05-11 09:32 -0700
            Re: Calculate/Interpolate size of y in  x^y = z  when you do know "number of  digits z" and  base  x? "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2015-05-11 19:45 +0200
              Re: Calculate/Interpolate size of y in  x^y = z  when you do know "number of  digits z" and  base  x? "Christoph M. Becker" <cmbecker69@arcor.de> - 2015-05-11 22:58 +0200
                Re: Calculate/Interpolate size of y in  x^y = z  when you do know "number of  digits z" and  base  x? "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2015-05-11 23:13 +0200

#27584 — Calculate/Interpolate size of y in x^y = z when you do know "number of digits z" and base x?

If i have a very bignumber z in decimal, i know the number of digits let us say 100 digits and base is x=64.

How can i interpolate, find a closeby y (where base is x). 
I do understand that i can add 1 to y until i reach the neighbourhood.

But is there any general rule to use to close in faster when you do know x and the number of digits in z?

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#27585

Den måndag 11 maj 2015 kl. 13:22:30 UTC+2 skrev jonas.t...@gmail.com:
> If i have a very bignumber z in decimal, i know the number of digits let us say 100 digits and base is x=64.
> 
> How can i interpolate, find a closeby y (where base is x). 
> I do understand that i can add 1 to y until i reach the neighbourhood.
> 
> But is there any general rule to use to close in faster when you do know x and the number of digits in z?

Sorry i was not clear i look for the closest integer of y bigger or smaller.

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#27586

Den måndag 11 maj 2015 kl. 13:28:06 UTC+2 skrev jonas.t...@gmail.com:
> Den måndag 11 maj 2015 kl. 13:22:30 UTC+2 skrev jonas.t...@gmail.com:
> > If i have a very bignumber z in decimal, i know the number of digits let us say 100 digits and base is x=64.
> > 
> > How can i interpolate, find a closeby y (where base is x). 
> > I do understand that i can add 1 to y until i reach the neighbourhood.
> > 
> > But is there any general rule to use to close in faster when you do know x and the number of digits in z?
> 
> Sorry i was not clear i look for the closest integer of y bigger or smaller.

But maybe assuming y is large like 1000 doing a search closing in by setting min and max is faster, than doing the calculation using logaritms?

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#27587

jonas.thornvall@gmail.com writes:

> Den måndag 11 maj 2015 kl. 13:28:06 UTC+2 skrev jonas.t...@gmail.com:
>> Den måndag 11 maj 2015 kl. 13:22:30 UTC+2 skrev jonas.t...@gmail.com:
>> > If i have a very bignumber z in decimal, i know the number of
>> > digits let us say 100 digits and base is x=64.
>> > 
>> > How can i interpolate, find a closeby y (where base is x). 
>> > I do understand that i can add 1 to y until i reach the neighbourhood.
>> > 
>> > But is there any general rule to use to close in faster when you
>> > do know x and the number of digits in z?
>> 
>> Sorry i was not clear i look for the closest integer of y bigger or smaller.
>
> But maybe assuming y is large like 1000 doing a search closing in by
> setting min and max is faster, than doing the calculation using
> logaritms?

It depends on how y is represented.  You say it is "in decimal".  If
that means it's a string then you just find the . and remove any
trailing digits.  This is so obvious that it can't be whay you mean.
How is z stored in the program?

-- 
Ben.

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#27588

Den måndag 11 maj 2015 kl. 14:56:28 UTC+2 skrev Ben Bacarisse:
> jonas.thornvall@gmail.com writes:
> 
> > Den måndag 11 maj 2015 kl. 13:28:06 UTC+2 skrev jonas.t...@gmail.com:
> >> Den måndag 11 maj 2015 kl. 13:22:30 UTC+2 skrev jonas.t...@gmail.com:
> >> > If i have a very bignumber z in decimal, i know the number of
> >> > digits let us say 100 digits and base is x=64.
> >> > 
> >> > How can i interpolate, find a closeby y (where base is x). 
> >> > I do understand that i can add 1 to y until i reach the neighbourhood.
> >> > 
> >> > But is there any general rule to use to close in faster when you
> >> > do know x and the number of digits in z?
> >> 
> >> Sorry i was not clear i look for the closest integer of y bigger or smaller.
> >
> > But maybe assuming y is large like 1000 doing a search closing in by
> > setting min and max is faster, than doing the calculation using
> > logaritms?
> 
> It depends on how y is represented.  You say it is "in decimal".  If
> that means it's a string then you just find the . and remove any
> trailing digits.  This is so obvious that it can't be whay you mean.
> How is z stored in the program?
> 
> -- 
> Ben.

An example using a small integer we search 2188 and base is 3. 

So 2188=3^y   
y is an integer.

I think mathetmaticians use logarithms for this kind of problem, but i am not sure that is fastest approach. Maybe a search algorithm, or other approaches are faster when one know the number of digits?

In this case the seareched number would be y=7 since i search (min?) the smaller value, not y=8 (max?) the bigger value. 

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#27589

Den måndag 11 maj 2015 kl. 15:12:38 UTC+2 skrev jonas.t...@gmail.com:
> Den måndag 11 maj 2015 kl. 14:56:28 UTC+2 skrev Ben Bacarisse:
> > jonas.thornvall@gmail.com writes:
> > 
> > > Den måndag 11 maj 2015 kl. 13:28:06 UTC+2 skrev jonas.t...@gmail.com:
> > >> Den måndag 11 maj 2015 kl. 13:22:30 UTC+2 skrev jonas.t...@gmail.com:
> > >> > If i have a very bignumber z in decimal, i know the number of
> > >> > digits let us say 100 digits and base is x=64.
> > >> > 
> > >> > How can i interpolate, find a closeby y (where base is x). 
> > >> > I do understand that i can add 1 to y until i reach the neighbourhood.
> > >> > 
> > >> > But is there any general rule to use to close in faster when you
> > >> > do know x and the number of digits in z?
> > >> 
> > >> Sorry i was not clear i look for the closest integer of y bigger or smaller.
> > >
> > > But maybe assuming y is large like 1000 doing a search closing in by
> > > setting min and max is faster, than doing the calculation using
> > > logaritms?
> > 
> > It depends on how y is represented.  You say it is "in decimal".  If
> > that means it's a string then you just find the . and remove any
> > trailing digits.  This is so obvious that it can't be whay you mean.
> > How is z stored in the program?
> > 
> > -- 
> > Ben.
> 
> An example using a small integer we search 2188 and base is 3. 
> 
> So 2188=3^y   
> y is an integer.
> 
> I think mathetmaticians use logarithms for this kind of problem, but i am not sure that is fastest approach. Maybe a search algorithm, or other approaches are faster when one know the number of digits?
> 
> In this case the seareched number would be y=7 since i search (min?) the smaller value, not y=8 (max?) the bigger value.

I think i had some formula selfinvented when i did this years ago, setting the startvalue for search dependent upon the digits of number and the base.

Is there away approximate y closely when you know the base=x and the number of digits in z?
Really don't remember.

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#27602

jonas.thornvall@gmail.com writes:
<snip>
> An example using a small integer we search 2188 and base is 3. 
>
> So 2188=3^y   
> y is an integer.

I don't think that was obvious, but I suspect you don't need to know
this number.  You posted some code the uses this number but it was more
complicated than it needed to be.

> I think mathetmaticians use logarithms for this kind of problem, but i
> am not sure that is fastest approach. Maybe a search algorithm, or
> other approaches are faster when one know the number of digits?

If you use the number of digits, you *are* using logarithms.  That's
what a logarithm is.

<snip>
-- 
Ben.

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#27590

jonas.thornvall@gmail.com wrote on 11 mei 2015 in comp.lang.javascript:

> Subject: Calculate/Interpolate size of y in  x^y = z  when you do know 
"number of  digits z" and  base  x?

Please do not use the subject line for your Q,
or at least repeat it in the text.

Is "size of y" not the same as "value of y",
and if not, why not? 

> If i have a very bignumber z in decimal, i know the number of digits let
> us say 100 digits and base is x=64. 

"Very big number", bignumbers [as all substantives] cannot be "very".

What do you mean by "decimal" if the base is 64?

Doesn't "decimal" mean base=10? 

> How can i interpolate, find a closeby y (where base is x).

You are asking for a value, values have no base.
 
> I do understand that i can add 1 to y until i reach the neighbourhood.

Welcome to the neighborhood. 

The neighborhood of what?
 
> But is there any general rule to use to close in faster when you do know x 
> and the number of digits in z?

Sorry?

-- 
Evertjan.
The Netherlands.
(Please change the x'es to dots in my emailaddress)

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#27591

Den måndag 11 maj 2015 kl. 15:19:51 UTC+2 skrev Evertjan.:
> jonas.thornvall@gmail.com wrote on 11 mei 2015 in comp.lang.javascript:
> 
> > Subject: Calculate/Interpolate size of y in  x^y = z  when you do know 
> "number of  digits z" and  base  x?
> 
> Please do not use the subject line for your Q,
> or at least repeat it in the text.
> 
> Is "size of y" not the same as "value of y",
> and if not, why not? 
> 
> > If i have a very bignumber z in decimal, i know the number of digits let
> > us say 100 digits and base is x=64. 
> 
> "Very big number", bignumbers [as all substantives] cannot be "very".
> 
> What do you mean by "decimal" if the base is 64?
> 
> Doesn't "decimal" mean base=10? 
> 
> > How can i interpolate, find a closeby y (where base is x).
> 
> You are asking for a value, values have no base.
>  
> > I do understand that i can add 1 to y until i reach the neighbourhood.
> 
> Welcome to the neighborhood. 
> 
> The neighborhood of what?
>  
> > But is there any general rule to use to close in faster when you do know x 
> > and the number of digits in z?
> 
> Sorry?
> 
> -- 
> Evertjan.
> The Netherlands.
> (Please change the x'es to dots in my emailaddress)

An example using a small integer we search 2188 and base is 3.

So 2188=3^y  
y is an integer.

In this case the seareched *integer* would be y=7 since i search (min?) the smaller value, not y=8 (max?) the bigger value.

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#27592

Den måndag 11 maj 2015 kl. 15:19:51 UTC+2 skrev Evertjan.:
> jonas.thornvall@gmail.com wrote on 11 mei 2015 in comp.lang.javascript:
> 
> > Subject: Calculate/Interpolate size of y in  x^y = z  when you do know 
> "number of  digits z" and  base  x?
> 
> Please do not use the subject line for your Q,
> or at least repeat it in the text.
> 
> Is "size of y" not the same as "value of y",
> and if not, why not? 
> 
> > If i have a very bignumber z in decimal, i know the number of digits let
> > us say 100 digits and base is x=64. 
> 
> "Very big number", bignumbers [as all substantives] cannot be "very".
> 
> What do you mean by "decimal" if the base is 64?
> 
> Doesn't "decimal" mean base=10? 
> 
> > How can i interpolate, find a closeby y (where base is x).
> 
> You are asking for a value, values have no base.
>  
> > I do understand that i can add 1 to y until i reach the neighbourhood.
> 
> Welcome to the neighborhood. 
> 
> The neighborhood of what?
>  
> > But is there any general rule to use to close in faster when you do know x 
> > and the number of digits in z?
> 
> Sorry?
> 
> -- 
> Evertjan.
> The Netherlands.
> (Please change the x'es to dots in my emailaddress)

By the way the baseconverter do support bignumbers now anybase anysize of number.

Now it would be nice with some speed, doing it the fastest way searching the correct digitplace. I think that will be faster than calculate using logarithms.

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#27593

jonas.thornvall@gmail.com wrote on 11 mei 2015 in comp.lang.javascript:

> Den måndag 11 maj 2015 kl. 15:19:51 UTC+2 skrev Evertjan.:
>> jonas.thornvall@gmail.com wrote on 11 mei 2015 in comp.lang.javascript:
>> 
>> > Subject: Calculate/Interpolate size of y in  x^y = z  when you do kno
> w 
>> "number of  digits z" and  base  x?
>> 
>> Please do not use the subject line for your Q,
>> or at least repeat it in the text.
>> 
>> Is "size of y" not the same as "value of y",
>> and if not, why not? 
>> 
>> > If i have a very bignumber z in decimal, i know the number of digits
>> > le 
> t
>> > us say 100 digits and base is x=64. 
>> 
>> "Very big number", bignumbers [as all substantives] cannot be "very".
>> 
>> What do you mean by "decimal" if the base is 64?
>> 
>> Doesn't "decimal" mean base=10? 
>> 
>> > How can i interpolate, find a closeby y (where base is x).
>> 
>> You are asking for a value, values have no base.
>>  
>> > I do understand that i can add 1 to y until i reach the
>> > neighbourhood. 
>> 
>> Welcome to the neighborhood. 
>> 
>> The neighborhood of what?
>>  
>> > But is there any general rule to use to close in faster when you do
>> > kno 
> w x 
>> > and the number of digits in z?
>> 
>> Sorry?

[Signature removed, as I asked you to do several times]
 
> By the way the baseconverter do support bignumbers now anybase anysize
> of number. 
> 
> Now it would be nice with some speed, doing it the fastest way searching
> the correct digitplace. I think that will be faster than calculate using
> logarithms. 

Do you never interact with people?

You are not answering my questions about the request YOU made.

It seems you are not interested in communicating with us,
because if you responde, you possibly did not even read the posting you are 
responding on.

And in most cases you are just responding to your own postings.

What is the matter with you? 

-- 
Evertjan.
The Netherlands.
(Please change the x'es to dots in my emailaddress)

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#27594

Den måndag 11 maj 2015 kl. 18:19:00 UTC+2 skrev Evertjan.:
> jonas.thornvall@gmail.com wrote on 11 mei 2015 in comp.lang.javascript:
> 
> > Den måndag 11 maj 2015 kl. 15:19:51 UTC+2 skrev Evertjan.:
> >> jonas.thornvall@gmail.com wrote on 11 mei 2015 in comp.lang.javascript:
> >> 
> >> > Subject: Calculate/Interpolate size of y in  x^y = z  when you do kno
> > w 
> >> "number of  digits z" and  base  x?
> >> 
> >> Please do not use the subject line for your Q,
> >> or at least repeat it in the text.
> >> 
> >> Is "size of y" not the same as "value of y",
> >> and if not, why not? 
> >> 
> >> > If i have a very bignumber z in decimal, i know the number of digits
> >> > le 
> > t
> >> > us say 100 digits and base is x=64. 
> >> 
> >> "Very big number", bignumbers [as all substantives] cannot be "very".
> >> 
> >> What do you mean by "decimal" if the base is 64?
> >> 
> >> Doesn't "decimal" mean base=10? 
> >> 
> >> > How can i interpolate, find a closeby y (where base is x).
> >> 
> >> You are asking for a value, values have no base.
> >>  
> >> > I do understand that i can add 1 to y until i reach the
> >> > neighbourhood. 
> >> 
> >> Welcome to the neighborhood. 
> >> 
> >> The neighborhood of what?
> >>  
> >> > But is there any general rule to use to close in faster when you do
> >> > kno 
> > w x 
> >> > and the number of digits in z?
> >> 
> >> Sorry?
> 
> [Signature removed, as I asked you to do several times]
>  
> > By the way the baseconverter do support bignumbers now anybase anysize
> > of number. 
> > 
> > Now it would be nice with some speed, doing it the fastest way searching
> > the correct digitplace. I think that will be faster than calculate using
> > logarithms. 
> 
> Do you never interact with people?
> 
> You are not answering my questions about the request YOU made.
> 
> It seems you are not interested in communicating with us,
> because if you responde, you possibly did not even read the posting you are 
> responding on.
> 
> And in most cases you are just responding to your own postings.
> 
> What is the matter with you? 
> 
> -- 
> Evertjan.
> The Netherlands.
> (Please change the x'es to dots in my emailaddress)

Oh i did but you are not really interested.
One more time for Evertjan
An example using a small integer we search 2188 and base is 3.

So 2188=3^y  
y is an integer.

In this case the seareched *integer* would be y=7 since i search (min?) the smaller value, not y=8 (max?) the bigger value.

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#27596

jonas.thornvall@gmail.com wrote on 11 mei 2015 in comp.lang.javascript:

> Den måndag 11 maj 2015 kl. 18:19:00 UTC+2 skrev Evertjan.:
>> jonas.thornvall@gmail.com wrote on 11 mei 2015 in comp.lang.javascript:
>> 
>> > Den måndag 11 maj 2015 kl. 15:19:51 UTC+2 skrev Evertjan.:
>> >> jonas.thornvall@gmail.com wrote on 11 mei 2015 in
>> >> comp.lang.javascript 
>:
>> >> 
>> >> > Subject: Calculate/Interpolate size of y in  x^y = z  when you do 
> kno
>> > w 
>> >> "number of  digits z" and  base  x?
>> >> 
>> >> Please do not use the subject line for your Q,
>> >> or at least repeat it in the text.
>> >> 
>> >> Is "size of y" not the same as "value of y",
>> >> and if not, why not? 
>> >> 
>> >> > If i have a very bignumber z in decimal, i know the number of
>> >> > digits le 
>> > t
>> >> > us say 100 digits and base is x=64. 
>> >> 
>> >> "Very big number", bignumbers [as all substantives] cannot be
>> >> "very". 
>> >> 
>> >> What do you mean by "decimal" if the base is 64?
>> >> 
>> >> Doesn't "decimal" mean base=10? 
>> >> 
>> >> > How can i interpolate, find a closeby y (where base is x).
>> >> 
>> >> You are asking for a value, values have no base.
>> >>  
>> >> > I do understand that i can add 1 to y until i reach the
>> >> > neighbourhood. 
>> >> 
>> >> Welcome to the neighborhood. 
>> >> 
>> >> The neighborhood of what?
>> >>  
>> >> > But is there any general rule to use to close in faster when you
>> >> > do kno 
>> > w x 
>> >> > and the number of digits in z?
>> >> 
>> >> Sorry?
>> 
>> [Signature removed, as I asked you to do several times]
>>  
>> > By the way the baseconverter do support bignumbers now anybase
>> > anysize of number. 
>> > 
>> > Now it would be nice with some speed, doing it the fastest way
>> > searchin 
> g
>> > the correct digitplace. I think that will be faster than calculate
>> > usin 
> g
>> > logarithms. 
>> 
>> Do you never interact with people?
>> 
>> You are not answering my questions about the request YOU made.
>> 
>> It seems you are not interested in communicating with us,
>> because if you responde, you possibly did not even read the posting you
>> a 
> re 
>> responding on.
>> 
>> And in most cases you are just responding to your own postings.
>> 
>> What is the matter with you? 
>> 
>> -- 
>> Evertjan.
>> The Netherlands.
>> (Please change the x'es to dots in my emailaddress)
> 
> Oh i did but you are not really interested.
> One more time for Evertjan
> An example using a small integer we search 2188 and base is 3.
> 
> So 2188=3^y  
> y is an integer.
> 
> In this case the seareched *integer* would be y=7 since i search (min?)
> the smaller value, not y=8 (max?) the bigger value. 

Perhaps an interesting text, but not an answer to one of my Qs.
So not what one can call an answer at all.

I asked five questions, see above, you gave only one answer,
which was not an answer to one of that five.

Then in the response I asked a sixth question,
you did not answer that either.

My conclusion holds, that you do not even read the responses on your Qs,
and only are buzy with your own idea's.

> Oh i did but you are not really interested.

How do you know, as you do not communicate?

-- 
Evertjan.
The Netherlands.
(Please change the x'es to dots in my emailaddress)

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#27603

Evertjan. wrote:

> Perhaps an interesting text, but not an answer to one of my Qs.
> So not what one can call an answer at all.
> 
> I asked five questions, see above, you gave only one answer,
> which was not an answer to one of that five.
> 
> Then in the response I asked a sixth question,
> you did not answer that either.

Don't forget that this is Usenet, and not a paid helpdesk.

-- 
Christoph M. Becker

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#27604

"Christoph M. Becker" <cmbecker69@arcor.de> wrote on 11 mei 2015 in 
comp.lang.javascript:

> Evertjan. wrote:
> 
>> Perhaps an interesting text, but not an answer to one of my Qs.
>> So not what one can call an answer at all.
>> 
>> I asked five questions, see above, you gave only one answer,
>> which was not an answer to one of that five.
>> 
>> Then in the response I asked a sixth question,
>> you did not answer that either.
> 
> Don't forget that this is Usenet, and not a paid helpdesk.

Indeed, so the OP should answer the Q of the ones who try to help,
and not reply with unrelated stuff and without reading the responses to the 
OQ and reacting on those.



-- 
Evertjan.
The Netherlands.
(Please change the x'es to dots in my emailaddress)

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