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What does the slash mean in help() output?
...self after the last parameter, indented the same as the parameter lines.
and the (very recent addition to) the Python FAQ:
A slash in the argument list of a function denotes that the parameters prior to it are positional-only. Positional-only parameters are the ones without an externally-usabl...
Reshaping data.frame from wide to long format
...alues (as a result of the , in the numbers). You can repair that with gsub and as.numeric:
long$value <- as.numeric(gsub(",", "", long$value))
Or directly with data.table or dplyr:
# data.table
long <- melt(setDT(wide),
id.vars = c("Code","Country"),
variable.name...
Best way to convert an ArrayList to a string
...ny fast way to do this? You could loop through it (or remove each element) and concatenate it to a String but I think this will be very slow.
...
HTML5 canvas ctx.fillText won't do line breaks?
...rs in the text you could simulate it by splitting the text at the newlines and calling multiple times the fillText()
Something like http://jsfiddle.net/BaG4J/1/
var c = document.getElementById('c').getContext('2d');
c.font = '11px Courier';
console.log(c);
var txt = 'line 1\nline 2\nthi...
Why is it not advisable to have the database and web server on the same machine?
...ning to Scott Hanselman's interview with the Stack Overflow team ( part 1 and 2 ), he was adamant that the SQL server and application server should be on separate machines. Is this just to make sure that if one server is compromised, both systems aren't accessible? Do the security concerns outwe...
Understanding dispatch_async
...e background.
For instance, if I am downloading a file from the internet and I want to update the user on the progress of the download, I will run the download in the priority default queue and update the UI in the main queue asynchronously.
dispatch_async(dispatch_get_global_queue( DISPATCH_QUEU...
What exactly do “u” and “r” string flags do, and what are raw string literals?
...no "escape sequences" to represent newlines, tabs, backspaces, form-feeds, and so on. In normal string literals, each backslash must be doubled up to avoid being taken as the start of an escape sequence.
This syntax variant exists mostly because the syntax of regular expression patterns is heavy w...
Facebook Graph API v2.0+ - /me/friends returns empty, or only friends who also use my application
I am trying to get my friend name and ids with Graph API v2.0, but data returns empty:
7 Answers
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How to secure an ASP.NET Web API [closed]
...in JWT.
We have managed to apply HMAC authentication to secure Web API, and it worked okay. HMAC authentication uses a secret key for each consumer which both consumer and server both know to hmac hash a message, HMAC256 should be used. Most of the cases, hashed password of the consumer is used a...
Dual emission of constructor symbols
...? This class has no base. Why does it have a "complete object constructor" and a "base object constructor" for each?
This Q&A implies to me that this is simply a by-product of polymorphism support, even though it's not actually required in this case.
Note that c++filt used to include this info...