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Conditional import of modules in Python
...user is on is Windows or Linux. I take the OS name as input from the user. Now, is it correct to do the following?
3 Answer...
Standard deviation of a list
... function _sum rather than the built-in sum which I've used in its place.
Now we have for example:
>>> mean([1, 2, 3])
2.0
>>> stddev([1, 2, 3]) # population standard deviation
0.816496580927726
>>> stddev([1, 2, 3], ddof=1) # sample standard deviation
0.1
...
Calculate age given the birth date in the format YYYYMMDD
...on _calculateAge(birthday) { // birthday is a date
var ageDifMs = Date.now() - birthday.getTime();
var ageDate = new Date(ageDifMs); // miliseconds from epoch
return Math.abs(ageDate.getUTCFullYear() - 1970);
}
Disclaimer: This also has precision issues, so this cannot be completely tr...
Ruby: Easiest Way to Filter Hash Keys?
...
Symbols can be parsed with regular expressions nowadays IIRC.
– Andrew Grimm
Sep 15 '11 at 23:15
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How do I create a URL shortener?
...for example).
For this example, I will use 12510 (125 with a base of 10).
Now you have to convert 12510 to X62 (base 62).
12510 = 2×621 + 1×620 = [2,1]
This requires the use of integer division and modulo. A pseudo-code example:
digits = []
while num > 0
remainder = modulo(num, 62)
dig...
Overcoming “Display forbidden by X-Frame-Options”
...ks well in FF/Chrome/Opera but doesn't work in IE/Edge though. Anyone who knows something which will?
– Collector
Aug 18 '15 at 4:49
7
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Performance optimization strategies of last resort [closed]
...e of changes was this:
The first problem found was use of list clusters (now called "iterators" and "container classes") accounting for over half the time. Those were replaced with fairly simple code, bringing the time down to 20 seconds.
Now the largest time-taker is more list-building. As a perc...
PHP Fatal error: Using $this when not in object context
...
@Sarfraz it's better now. Sorry for pestering you, but as this became the accepted answer, I felt it necessary to point these things out :) Thanks for your patience.
– Gordon
Feb 28 '10 at 13:00
...
What does static_assert do, and what would you use it for?
...cks its condition at compilation. So if the condition you're asserting is known at compile time, use static_assert. If the condition won't be known until the program runs, use assert.
– Mike DeSimone
May 3 '13 at 4:50
...
Bogus foreign key constraint fail
...
On demand, now as an answer...
When using MySQL Query Browser or phpMyAdmin, it appears that a new connection is opened for each query (bugs.mysql.com/bug.php?id=8280), making it neccessary to write all the drop statements in one query...