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Should I instantiate instance variables on declaration or in the constructor?
...lass. Instead, using Dependency Injection is preferable - i.e. letting someone else (another class/framework) instantiate and inject the dependencies in your class.
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How to duplicate a git repository? (without forking)
I have two repositories, and I need to copy whole of one onto the other empty one which has different access levels from the first one. The copy and the mother repository should not be linked together.
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IEnumerable vs List - What to Use? How do they work?
...3 types. stackoverflow.com/questions/2876616/…
– Bronek
Jan 6 '14 at 20:55
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@Bronek The answer...
How do I edit an existing tag message in git?
... `# get the second to last date, as the last one is the commit date` \
> git tag tag1 tag1^{} -a -f # finally, update the tag message, but save the date of the old one
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> git rev-list --objects -g --no-walk --all
6bdcc34...
How do I create a new GitHub repo from a branch in an existing repo?
...at you don't need to create a repo on Github, you can just push to a local one (i.e. git init instead of Github > New > ...)
– OJFord
Apr 19 '16 at 12:19
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For each row return the column name of the largest value
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One option using your data (for future reference, use set.seed() to make examples using sample reproducible):
DF <- data.frame(V1=c(2,8,1),V2=c(7,3,5),V3=c(9,6,4))
colnames(DF)[apply(DF,1,which.max)]
[1] "V3" "V1" "V2"
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How to get first 5 characters from string [duplicate]
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An alternative way to get only one character.
$str = 'abcdefghij';
echo $str{5};
I would particularly not use this, but for the purpose of education. We can use that to answer the question:
$newString = '';
for ($i = 0; $i < 5; $i++) {
$newString ....
How to fire AJAX request Periodically?
...setInterval(). If the first request hasn't completed and you start another one, you could end up in a situation where you have multiple requests that consume shared resources and starve each other. You can avoid this problem by waiting to schedule the next request until the last one has completed:
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Speed up the loop operation in R
....time(dayloop2(X))
Result is
You can see that your version depends exponentially from nrow(X). Modified version has linear relation, and simple lm model predict that for 850,000 rows computation takes 6 minutes and 10 seconds.
Power of vectorization
As Shane and Calimo states in theirs answer...
How to request a random row in SQL?
... -1 for relying on order by rand() or equivalents in all dbs :|. also mentioned here.
– AD7six
May 26 '14 at 9:27
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