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Grouping functions (tapply, by, aggregate) and the *apply family
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10 Answers
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Javascript: negative lookbehind equivalent?
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Lookbehind Assertions got accepted into the ECMAScript specification in 2018.
Positive lookbehind usage:
console.log(
"$9.99 €8.47".match(/(?<=\$)\d+(\.\d*)?/) // Matches "9.99"
);
Negative lookbehind usage:
console.log(
"$9.99 €8.47".match(/(?<!\$)\d+(?:\.\d*)/)...
Reset select2 value and show placeholder
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edited Jan 24 '17 at 15:20
Hakan Fıstık
9,09888 gold badges5757 silver badges8686 bronze badges
answe...
Places where JavaBeans are used?
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edited Jun 20 at 9:12
Community♦
111 silver badge
answered Nov 13 '09 at 13:36
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Logging levels - Logback - rule-of-thumb to assign log levels
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edited Aug 9 '19 at 5:20
Chege
29544 silver badges88 bronze badges
answered Nov 5 '11 at 16:40
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HTML 5 Favicon - Support?
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The above covers IE up to IE 9. IE 11 accepts PNG favicons, however, IE 10 does not. Also IE 10 does not read conditional comments thus IE 10 won't show a favicon. With IE 11 and Edge available I don't see IE 10 in widespread use, so I ignore this browser.
For the rest of the browsers we are goin...
ggplot with 2 y axes on each side and different scales
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109
Sometimes a client wants two y scales. Giving them the "flawed" speech is often pointless. But ...
Android ADB device offline, can't issue commands
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140
I just got the same problem today after my Nexus 7 and Galaxy Nexus were updated to Android 4.2....
How can I extend typed Arrays in Swift?
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10 Answers
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Different ways of clearing lists
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>>> b = a
>>> del a[:] # equivalent to del a[0:len(a)]
>>> print(a)
[]
>>> print(b)
[]
>>> a is b
True
You could also do:
>>> a[:] = []
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