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Concatenate a vector of strings/character
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You can use stri_paste function with collapse parameter from stringi package like this:
stri_paste(letters, collapse='')
## [1] "abcdefghijklmnopqrstuvwxyz"
And some benchmarks:
require(microbenchmark)
test <- stri_rand_lipsum(100)
microbenchmark(stri_paste(test, collapse=...
Code signing certificate for open-source projects?
...o longer free - the reference to open source code signing has been removed from the test certificates page, and there is now a separate product page en.sklep.unizeto.pl/data-safety/code-signing-certificates/…. At €14 they're much cheaper than other certificates though. The signup process seems t...
How can you diff two pipelines in Bash?
...names like /dev/fd/63 to get a filename that the command can open and read from to actually read from an already-open file descriptor that bash set up before exec'ing the command. (i.e. bash uses pipe(2) before fork, and then dup2 to redirect from the output of quux to an input file descriptor for ...
Why does isNaN(“ ”) (string with spaces) equal false?
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@Kooilnc not to take away even slightly from the wackiness of javascript, but these NaNs are just obeying the IEEE 754 floating point standard. You can read ALL about it as usual on the big W: en.wikipedia.org/wiki/NaN
– Spike0xff
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How can I get query string values in JavaScript?
...r the hash resides in the window.location.hash property, which is separate from the window.location.search property. If the hash changes, it doesn't affect the querystring at all.
– Andy E
Jul 14 '10 at 9:20
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Best way to structure a tkinter application? [closed]
...ually create the main window until the very last step. I prefer inheriting from tk.Frame just because I typically start by creating a frame, but it is by no means necessary.
If your app has additional toplevel windows, I recommend making each of those a separate class, inheriting from tk.Toplevel...
Java Immutable Collections
From Java 1.6 Collection Framework documentation :
6 Answers
6
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Why Would I Ever Need to Use C# Nested Classes [duplicate]
...ll as protected of course).
Basically, if you only need to use this class from within the "parent" class (in terms of scope), then it is usually appropiate to define it as a nested class. If this class might need to be used from without the assembly/library, then it is usually more convenient to th...
What do the different readystates in XMLHttpRequest mean, and how can I use them?
...en sent
3 The request is in process
4 The request is complete
(from https://www.w3schools.com/js/js_ajax_http_response.asp)
In practice you almost never use any of them except for 4.
Some XMLHttpRequest implementations may let you see partially received responses in responseText when r...
When is assembly faster than C?
...ed a lot.
C doesn't have a full-multiplication operator (2N-bit result from N-bit inputs). The usual way to express it in C is to cast the inputs to the wider type and hope the compiler recognizes that the upper bits of the inputs aren't interesting:
// on a 32-bit machine, int can hold 32-bit...