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Opposite of %in%: exclude rows with values specified in a vector
... use
`%not in%` <- function (x, table) is.na(match(x, table, nomatch=NA_integer_))
Another way is:
function (x, table) match(x, table, nomatch = 0L) == 0L
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Generating random integer from a range
...uch better ways of getting something that is uniformly distributed and actually random.
– Mgetz
Sep 12 '13 at 19:14
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Increasing the maximum number of TCP/IP connections in Linux
...local_port_range = 32768 61000
net.ipv4.tcp_fin_timeout = 60
This basically means your system cannot consistently guarantee more than (61000 - 32768) / 60 = 470 sockets per second. If you are not happy with that, you could begin with increasing the port_range. Setting the range to 15000 61000 is...
MySQL: Transactions vs Locking Tables
...is transferred. And the bank's account, into which they'll happily deposit all the service fees charged on the transaction. Given (as everyone knows these days) that banks are extraordinarily stupid, let's say their system works like this:
$balance = "GET BALANCE FROM your ACCOUNT";
if ($balance &l...
switch / pattern matching idea
... and some very smart people have done some very cool things in C#, but actually using it feels heavy.
What I have ended up using often (across-projects) in C#:
Sequence functions, via extension methods for IEnumerable. Things like ForEach or Process ("Apply"? -- do an action on a sequence item as...
Preventing scroll bars from being hidden for MacOS trackpad users in WebKit/Blink
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One thing to mention is that, in my testing and a really old comment by someone else it seems you can't have an always-on scrollbar AND the momentum-like scrolling that people are used to with iOS. Doing the momentum-scrolling CSS caused my custom scrollbars to disappear.
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Rails find_or_create_by more than one attribute?
There is a handy dynamic attribute in active-record called find_or_create_by:
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Difference between socket and websocket?
...kets are different than websockets . It seems like they're only conceptually similar.
5 Answers
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How to change MenuItem icon in ActionBar programmatically
...thod
menu.getItem(0).setIcon(ContextCompat.getDrawable(this, R.drawable.ic_launcher));
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How do I make an http request using cookies on Android?
...ookies when I make subsequent requests). It'd be nice to preserve any and all cookies, but really the only one I care about is the session cookie.
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