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Generate random numbers following a normal distribution in C/C++
.... Except that BM uses one input RN per output, whereas CLT uses many more, etc... so the time to generate a uniform random # matters.
– greggo
Nov 14 '17 at 19:53
add a comme...
How to check internet access on Android? InetAddress never times out
... could run on main thread
- does not work on some old devices (Galays S3, etc.), it blocks a while if no internet is available.
B) Connect to a Socket on the Internet (advanced)
// TCP/HTTP/DNS (depending on the port, 53=DNS, 80=HTTP, etc.)
public boolean isOnline() {
try {
int timeou...
Find intersection of two nested lists?
... 3 filter returns an iterable instead of list, so you need to wrap filter calls with list():
c3 = [list(filter(lambda x: x in c1, sublist)) for sublist in c2]
Explanation:
The filter part takes each sublist's item and checks to see if it is in the source list c1.
The list comprehension is exec...
How do you remove duplicates from a list whilst preserving order?
...n seen or seen_add(x))]
Why assign seen.add to seen_add instead of just calling seen.add? Python is a dynamic language, and resolving seen.add each iteration is more costly than resolving a local variable. seen.add could have changed between iterations, and the runtime isn't smart enough to rule t...
Unable to simultaneously satisfy constraints, will attempt to recover by breaking constraint
...(13)-|[UIView:0x85a8fb0]...
This would be trailing horizontal constraint etc.
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How to Create Multiple Where Clause Query Using Laravel Eloquent?
... '<>', 'value_2'],
[COLUMN, OPERATOR, VALUE],
...
])
Personally I haven't found use-case for this over just multiple where calls, but fact is you can use it.
Since June 2014 you can pass an array to where
As long as you want all the wheres use and operator, you can group them this ...
Python: fastest way to create a list of n lists
...
The probably only way which is marginally faster than
d = [[] for x in xrange(n)]
is
from itertools import repeat
d = [[] for i in repeat(None, n)]
It does not have to create a new int object in every iteration and is about 15 % faster on my machine.
Edi...
Custom events in jQuery?
... best way. I know how to hook up events from the dom elements like 'click' etc, but I'm building a tiny javascript library/plugin to handle some preview functionality.
...
“Unknown class in Interface Builder file” error at runtime
...th it, and prints the warning.
By default, Objective-C targets will have -all_load -ObjC flags set by default, which will keep all of the symbols. But I had started with a C++ target, and didn't have that. Nevertheless, I found a way around this, which keeps the linker aggressive.
The hack I was...
Favourite performance tuning tricks [closed]
...bles
Build with triggers on the underlying tables
Build daily / hourly / etc.
Build ad-hoc
Build incrementally or teardown / rebuild
See what the query plan is with SET SHOWPLAN ON
See what’s actually happenning with SET STATS IO ON
Force an index using the pragma: (index: myindex)
Force th...