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In what areas might the use of F# be more appropriate than C#? [closed]
...sting and were easily able to reimplement the relevant code in F# for a 10,000× performance improvement. Due to the free-form nature of this product's GUI, the GUI designer and C# would not have been beneficial.
Much of our work revolves around numerical methods, including both our commercial libr...
SQL query to group by day
... the day created
for example, if the sale created on '2009-11-02 06:12:55.000',
dateadd(DAY,0, datediff(day,0, created)) return '2009-11-02 00:00:00.000'
select sum(amount) as total, dateadd(DAY,0, datediff(day,0, created)) as created
from sales
group by dateadd(DAY,0, datediff(day,0, created))
...
Regular expression that matches valid IPv6 addresses
...
You IPv4 regex does not match IPs like 127.000.000.001
– Kentzo
Mar 13 '14 at 12:48
22
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Rails: Is there a rails trick to adding commas to large numbers?
...xample:
#inside anywhere
ActiveSupport::NumberHelper.number_to_delimited(1000000) # => "1,000,000"
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Get DateTime.Now with milliseconds precision
...info: "{0:yyyyMMdd HH:mm:ss.fff}", DateTime.UtcNow -> 20180502 11:07:20.000 Win32.GetSystemTime(ref stime) -> 2018,2,5,11,7,20,0 (y m d h mm ss ms) I can create a instance of date time with milliseconds: var dt = new DateTime(2018, 5, 2, 19, 34, 55, 200); "{0:yyyyMMdd HH:mm:ss.fff}", dt -> ...
Why are static variables considered evil?
... your class, and then asked your class to execute a particular function 10,000 times, once those 10,000 calls were done, and you delete your references to the single instance, all your static variables could be garbage collected and reused.
Prevents certain re-use:
Also, static methods cannot be u...
What is “2's Complement”?
...ame thing, but switch the role of 0's and 1's (so instead of starting with 0000, start with 1111 - that's the "complement" part).
Let's try it with a mini-byte of 4 bits (we'll call it a nibble - 1/2 a byte).
0000 - zero
0001 - one
0010 - two
0011 - three
0100 to 0111 - four to seven
That's as fa...
Common MySQL fields and their appropriate data types
... Also, integers only support up to value of 2 billion. That's 2,000,000,000. Which really isn't enough space when you want to store international phone numbers, complete with country code. I don't even see how you could find enough space to store a number like 655-405-4055 (6,554,054,05...
Replace non-numeric with empty string
...t still significantly faster than Regex. Given that that is benchmarking 1,000,000 replacements, the effective difference between the StringBuilder and LINQ solutions for most scenarios is probably neglible.
– Chris Pratt
May 15 '18 at 23:45
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How do you check in python whether a string contains only numbers?
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This isn't correct though, no? int("1_000") doesn't lead to an error, for example.
– AMC
Jun 2 at 23:08
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