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How to set Oracle's Java as the default Java in Ubuntu?
How do I change the value of JAVA_HOME in Ubuntu to point to Oracle's Java?
8 Answers
...
Paste multiple columns together
...c('d', 'e', 'f'),
'd' = c('g', 'h', 'i'))
tidyr::unite_(data, paste(colnames(data)[-1], collapse="_"), colnames(data)[-1])
a b_c_d
1 1 a_d_g
2 2 b_e_h
3 3 c_f_i
Edit: Exclude first column, everything else gets pasted.
# tidyr_0.6.3
unite(data, newCol, -a)
# or by colum...
Why does Python code use len() function instead of a length method?
...
Strings do have a length method: __len__()
The protocol in Python is to implement this method on objects which have a length and use the built-in len() function, which calls it for you, similar to the way you would implement __iter__() and use the built-in ...
Window.open and pass parameters by post method
...
@Guffa any way to also simulate the behavior of target="_blank"?
– everton
Jan 15 '14 at 20:31
2
...
Gradle does not find tools.jar
...o use the package tools.jar, which is in the lib folder from the jdk (1.6.0_26 in my case).
21 Answers
...
Remove last character from string. Swift language
...answered Jul 24 '14 at 11:28
gui_dosgui_dos
1,19377 silver badges55 bronze badges
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SQL Server Regular expressions in T-SQL
...oks Online)
Wildcard Meaning
% Any string of zero or more characters.
_ Any single character.
[ ] Any single character within the specified range
(for example, [a-f]) or set (for example, [abcdef]).
[^] Any single character not within the specified range
(for example, [^a - f]) or s...
What is the JavaScript convention for no operation?
...noop = ()=>{};
const noopProto = Function.prototype;
function test (_noop, iterations) {
const before = performance.now();
for(let i = 0; i < iterations; i++) _noop();
const after = performance.now();
const elapsed = after - before;
console.info(`${elapsed.toFixed(...
ExpressJS How to structure an application?
...ike to structure a medium-sized express.js application.
focusaurus/express_code_structure is the repo with the latest code for this. Pull requests welcome.
Here's a snapshot of the README since stackoverflow doesn't like just-a-link answers. I'll make some updates as this is a new project that I'l...
iOS 7 - Status bar overlaps the view
...patibility.
NSUInteger DeviceSystemMajorVersion() {
static NSUInteger _deviceSystemMajorVersion = -1;
static dispatch_once_t onceToken;
dispatch_once(&onceToken, ^{
NSString *systemVersion = [UIDevice currentDevice].systemVersion;
_deviceSystemMajorVersion = [[syste...