Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]
Groups > comp.lang.java.programmer > #34337
| From | Gene Wirchenko <genew@telus.net> |
|---|---|
| Newsgroups | comp.lang.java.programmer |
| Subject | Re: Mathematics, Java, good enough |
| Date | 2016-05-17 14:17 -0700 |
| Organization | A noiseless patient Spider |
| Message-ID | <de2njbp07clfvncvpbspr7b7a0j6f1moj5@4ax.com> (permalink) |
| References | <nhesp7$hn7$1@dont-email.me> <words-20160517152443@ram.dialup.fu-berlin.de> <nhfjd2$6da$1@dont-email.me> <nhfmi0$k4d$1@dont-email.me> |
On Tue, 17 May 2016 14:09:25 -0400, Eric Sosman
<esosman@comcast-dot-net.invalid> wrote:
>On 5/17/2016 1:15 PM, Duncan Idaho wrote:
>> On 17/05/16 15:43, Stefan Ram wrote:
>>> Duncan Idaho <duncan@dunenoemail.com> writes:
>>>> how many strings of length L are possible from
>>> ...
>>>> a set of characters S of cardinality C
>>>
>>> If an alphabet has C members, there are C^L words of length
>>> L over it, because for every word position, there are C choices,
>>> and the choices of positions multiply as one can easily see.
>>>
>>> For example, an octet of bit memory cells has java.lang.Math.pow
>>> ( 2, 8 ) possible states. A UHD screen with 24 bits of color can
>>> show java.math.BigInteger.valueOf( 2<<23 ).pow( 7680 * 4320 )
>>> different pictures.
>>
>> hmm
>>
>> That last one was too easy for you guys obviously :-)
>>
>> So what if I said how many *sets* of cardinality C are there in a set S
>> of cardinality SC
>>
>> Example
>> so where C = 8 then "ABCDEFGH" is good but "AABCDEFG" isn't
>
> Your terminology isn't too clear; what does "in" mean?
>
> But *if* you mean "How many 8-character strings can I make from
>a 62-character alphabet, with no repetitions?" that's an easy one:
>
> 62 * 61 * 60 * 59 * 58 * 57 * 56 * 55
>
>also known as
>
> 62! / (62-8)! ~= 1.4E14
Eric Sosman, DI did state "set" so order is not relevant so
divide your answer by 8!
Duncan Idaho, if you are going to ask any more questions like
this, I suggest that 1) you post your work first and 2) make the
problems interesting.
Sincerely,
Gene Wirchenko
Back to comp.lang.java.programmer | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread
Mathematics, Java, good enough Duncan Idaho <duncan@dunenoemail.com> - 2016-05-17 11:49 +0100
Re: Mathematics, Java, good enough Eric Douglas <e.d.programmer@gmail.com> - 2016-05-17 04:55 -0700
Re: Mathematics, Java, good enough Nigel Wade <nmw@ion.le.ac.uk> - 2016-05-17 12:56 +0100
Re: Mathematics, Java, good enough Nigel Wade <nmw@ion.le.ac.uk> - 2016-05-17 13:06 +0100
Re: Mathematics, Java, good enough Duncan Idaho <duncan@dunenoemail.com> - 2016-05-17 13:29 +0100
Re: Mathematics, Java, good enough Eric Sosman <esosman@comcast-dot-net.invalid> - 2016-05-17 09:54 -0400
Re: Mathematics, Java, good enough FredK <fred.l.kleinschmidt@gmail.com> - 2016-05-17 07:17 -0700
Re: Mathematics, Java, good enough FredK <fred.l.kleinschmidt@gmail.com> - 2016-05-17 07:29 -0700
Re: Mathematics, Java, good enough Eric Sosman <esosman@comcast-dot-net.invalid> - 2016-05-17 10:58 -0400
Re: Mathematics, Java, good enough Duncan Idaho <duncan@dunenoemail.com> - 2016-05-17 18:10 +0100
Re: Mathematics, Java, good enough Eric Sosman <esosman@comcast-dot-net.invalid> - 2016-05-17 14:02 -0400
Re: Mathematics, Java, good enough Eric Sosman <esosman@comcast-dot-net.invalid> - 2016-05-17 14:10 -0400
Re: Mathematics, Java, good enough Eric Douglas <e.d.programmer@gmail.com> - 2016-05-17 11:36 -0700
Re: Mathematics, Java, good enough Eric Sosman <esosman@comcast-dot-net.invalid> - 2016-05-17 16:12 -0400
Re: Mathematics, Java, good enough Eric Douglas <e.d.programmer@gmail.com> - 2016-05-17 13:56 -0700
Re: Mathematics, Java, good enough Gene Wirchenko <genew@telus.net> - 2016-05-17 14:13 -0700
Re: Mathematics, Java, good enough Duncan Idaho <duncan@dunenoemail.com> - 2016-05-18 05:06 +0100
Re: Mathematics, Java, good enough Eric Sosman <esosman@comcast-dot-net.invalid> - 2016-05-17 08:25 -0400
Re: Mathematics, Java, good enough Martin Gregorie <martin@address-in-sig.invalid> - 2016-05-17 12:24 +0000
Re: Mathematics, Java, good enough Duncan Idaho <duncan@dunenoemail.com> - 2016-05-17 18:15 +0100
Re: Mathematics, Java, good enough Jerry Stuckle <jstucklex@attglobal.net> - 2016-05-17 13:33 -0400
Re: Mathematics, Java, good enough Eric Sosman <esosman@comcast-dot-net.invalid> - 2016-05-17 14:09 -0400
Re: Mathematics, Java, good enough Gene Wirchenko <genew@telus.net> - 2016-05-17 14:17 -0700
Re: Mathematics, Java, good enough Eric Sosman <esosman@comcast-dot-net.invalid> - 2016-05-17 17:49 -0400
csiph-web