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Add new field to every document in a MongoDB collection
...field" : 1, "test" : "a" }
EDIT:
In case you want to add a new_field to all your collection, you have to use empty selector, and set multi flag to true (last param) to update all the documents
db.your_collection.update(
{},
{ $set: {"new_field": 1} },
false,
true
)
EDIT:
In the above ...
Convert data.frame column to a vector?
...
You do not need as.vector(), but you do need correct indexing: avector <- aframe[ , "a2"]
The one other thing to be aware of is the drop=FALSE option to [:
R> aframe <- data.frame(a1=c1:5, a2=6:10, a3=11:15)
R> aframe
a1 a2 a3
1 1 6 11
2 2 7 12
3 3 8 13
4 ...
How do you install Boost on MacOS?
How do you install Boost on MacOS?
Right now I can't find bjam for the Mac.
10 Answers
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How to find what code is run by a button or element in Chrome using Developer Tools
...ess the F11 key (Step In) until desired source code appears
Source code finally reached
In the jsFiddle sample provided above, I had to press F11 108 times before reaching the desired event handler/function
Your mileage may vary, depending on the version of jQuery (or framework library) used to bi...
How do I show a console output/window in a forms application?
...
You may also want to consider Log4net ( http://logging.apache.org/log4net/index.html ) for configuring log output in different configurations.
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Programmatically go back to the previous fragment in the backstack
...ening. In fragment example developer.android.com/training/basics/fragments/index.html they are not overiding onbackpressed event and yet they are able to backstack fragment. I have used trasaction.addToBackStack(null); but nothing happens. Can you explain why ?
– Murtaza K...
How to avoid 'cannot read property of undefined' errors?
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Catching all exceptions without re-throwing is bad, and generally using exceptions as part of the expected flow of execution is also not great -- even though in this case it's pretty well contained.
– hugo
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Simple argparse example wanted: 1 argument, 3 results
...or meddle with formatting lines on the screen or change option characters. All I want to do is "If arg is A, do this, if B do that, if none of the above show help and quit" .
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Bash function to find newest file matching pattern
... Your one liner is giving me right answer, but the "right" way is actually giving me the oldest file. Any idea why?
– NewNameStat
Apr 4 '19 at 21:59
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parseInt(null, 24) === 23… wait, what?
...t;> reduce(lambda x, y: x * 36 + y, [(string.digits + string.lowercase).index(x) for x in 'null'])
1112745
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