Re^2: Monte Carlo - Coin Toss

It is more idiomatic (and often simpler) to use Perl-style rather than C-style loops.

Yes, but it won't work if the numbers are too large for integers and have to use floating point. Then only C style loops will work.

my @collect = map 0, 0 .. NUM_TOSSES;
[download]

Why are you initializing @collect with NUM_TOSSES + 1 elements?

The idiomatic way to initialize @collect with NUM_TOSSES elements is usually:

my @collect = ( 0 ) x NUM_TOSSES;
[download]

for ($i = 0; $i < $numTosses+1; $i++) { foreach my $tailsCt ( 0 .. NUM_TOSSES )
[download]

You have an off-by-one error, it should be:

foreach my $tailsCt ( 0 .. NUM_TOSSES - 1 )
[download]

Update: oops, I misread the original code.

Comment on Re^2: Monte Carlo - Coin Toss Select or Download Code
Re^3: Monte Carlo - Coin Toss by ikegami (Pope) on Mar 12, 2011 at 08:18 UTC
Yes, but it won't work if the numbers are too large for integers and have to use floating point. If 2 billion loop iterations are not enough for you, you can always nest loops to multiple the range.	[reply]
Re^3: Monte Carlo - Coin Toss by Eliya (Priest) on Mar 12, 2011 at 10:40 UTC
You have an off-by-one error, it should be: ... No, `0 .. NUM_TOSSES` is correct here, because adding up NUM_TOSSES (with a single result being 0 or 1) can potentially produce values ranging from zero to NUM_TOSSES. Tossing a coin once can produce 0 or 1 tails; tossing a coin twice can produce 0, 1 or 2 tails; etc.	[reply] [d/l]
Re^3: Monte Carlo - Coin Toss by johngg (Abbot) on Mar 12, 2011 at 12:38 UTC
Why are you initializing @collect with NUM_TOSSES + 1 elements? The idiomatic way to initialize @collect with NUM_TOSSES elements is usually: `my @collect = ( 0 ) x NUM_TOSSES;` [download] As Eliya points out, 20 tosses could give 21 outcomes as regards the number of "tails" tossed, i.e. 0, 1, ... 19 or 20 so your way should be `my @collect = ( 0 ) x ( NUM_TOSSES + 1 );` [download] and I would agree that your way is perhaps more idiomatic. However, I felt that `my @collect = map 0, 0 .. NUM_TOSSES;` [download] better illustrated the relation between the numbers of tosses and outcomes. What do others think? Cheers, JohnGG	[reply] [d/l] [select]


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