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- bobbym
- 2012-07-31 01:55:30
Hi;
Go at your own pace. You did well.
- phrontister
- 2012-07-31 01:48:34
Hi Bobby,
That's really the only way I'll get anywhere with M for now. Anything that would require more dedicated study effort will have to wait until I get more time to be able to spend at it...but little by little I'm picking a few things up. Thanks for dangling the "extra credit" carrot...it motivated me. 
- bobbym
- 2012-07-31 01:39:48
Hi phrontister;
That is fine. It is okay to go from one language to another looking for the same type of commands in each language.
- phrontister
- 2012-07-30 23:44:11
Hi Bobby,
Here's my M code. As you'll see, I was thinking LB while coding M...but it works.
My initial code was slow because I was testing for '200 ones' from the first pick ( 
), but changing the test to commence after 199 picks reduced processing time to 1/7th of previous.
My LB code for 100,000 cycles took well over 9 hours c.f. M's 271 seconds.
Code:
In[1]:= Timing[sum = 0; c = 0; s = Table[0, {1000}];
N[While[c < 100000, t = 199; ss = s;
Do[ss[[RandomInteger[{1, 1000}]]] = 1, {t}]
While[Count[ss, 1] < 200, ss[[RandomInteger[{1, 1000}]]] = 1;t++];
sum = sum + t; c++]; sum/c]]
Out[1]= {270.985, 223.00152}So, again, just a touch > 223.
- bobbym
- 2012-07-30 21:11:39
Hi phrontister;
I got a shade over 223 also.
- anonimnystefy
- 2012-07-30 17:52:40
Hi phrontister
I started running 10 100000-cycles, but I wasn't at the computer long enough to check.
- phrontister
- 2012-07-30 16:56:21
Hi Bobby and stefy,
I've run several 10,000-cycle simulations in LB and each result was a smidge over 223.0. The result of a 100,000 cycle was 223.03524.
My Excel results varied more, but all were still only just < or > 223. I only tested up to about 1,000 cycles, which would account for the variation difference between the two programs.
- bobbym
- 2012-07-30 06:26:22
To get the sd we would have to run the simulation many times and use the formula. But by inspection you can see the dispersion is going to be small.
- anonimnystefy
- 2012-07-30 06:24:25
Oh. Okay.
- bobbym
- 2012-07-30 06:20:33
I do not know. But looking at the data the values are very close.
- anonimnystefy
- 2012-07-30 06:17:39
How small?
- bobbym
- 2012-07-30 06:16:11
Yes, it is quite small.
- anonimnystefy
- 2012-07-30 06:14:45
Standard deviation?
- bobbym
- 2012-07-30 06:13:17
Yes, it looks fine to me. The sd is very small on this problem.
- anonimnystefy
- 2012-07-30 06:11:00
Did you see the edited post 19?