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Counting the occurrences / frequency of array elements
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}
console.log(counts[5], counts[2], counts[9], counts[4]);
So, now your counts object can tell you what the count is for a particular number:
console.log(counts[5]); // logs '3'
If you want to get an array of members, just use the keys() functions
keys(counts); // returns ["5", "2", ...
Best way to detect Mac OS X or Windows computers with JavaScript or jQuery
...ft side when the user is on Mac and the right side when the user is on PC. Now I'm doing it by examining the user agent, but it can be too easily spoofed for reliable OS detection. Is there a surefire way to detect whether the OS on which the browser is running is Mac OS X or Windows? If not, what's...
C++, variable declaration in 'if' expression
...nd part (bool a = false) should be not be evaluated because it is already known that the final answer will be false. If (bool a = false) isn't evaluated, then what to do with code later on that uses a? Would we just not initialize the variable and leave it undefined? Would we initialize it to the...
How should I detect unnecessary #include files in a large C++ project?
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I don't know of any such tools, and I have thought about writing one in the past, but it turns out that this is a difficult problem to solve.
Say your source file includes a.h and b.h; a.h contains #define USE_FEATURE_X and b.h uses ...
End of support for python 2.7?
Is there a known date/timeframe when python 2.7 will not be supported any more in favor of python 3?
9 Answers
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Getting and removing the first character of a string
...ht back" "r" "ight back"
[[3]]
[1] "at yah" "a" "t yah"
Now, we can use the trusty sapply + [ method to pull out the desired substrings.
myFirstStrings <- sapply(myStrings, "[", 2)
myFirstStrings
[1] "h" "r" "a"
mySecondStrings <- sapply(myStrings, "[", 3)
mySecondStrings
[...
AWS Difference between a snapshot and AMI
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I don't know what you mean by "backed up an AMI image".
– Eric Hammond
Jul 13 '13 at 19:22
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What is the difference between hg forget and hg remove?
...in your working copy. The files are left behind as untracked files and can now optionally be ignored with a pattern in .hgignore.
In other words, I cannot tell if you used hg forget or hg remove when I pull from you. A file that you ran hg forget on will be deleted when I update to that changeset ...
How do you upload images to a gist?
...answered Nov 30 '18 at 15:14
ow3now3n
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How to 'git pull' into a branch that is not the current one?
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It's minutes long because a (now) untracked file would be overwritten by an earlier commit. So I have to copy the file, do the git stuff, then put it back. The 'minutes long' comes from my typing speed. (Yes I could script it but it was just to make a...