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Update MongoDB field using value of another field
..."name": { "$concat": ["$firstName", " ", "$lastName"]}}}
]
)
MongoDB 3.4+
In 3.4+ you can use $addFields and the $out aggregation pipeline operators.
db.collection.aggregate(
[
{ "$addFields": {
"name": { "$concat": [ "$firstName", " ", "$lastName" ] }
}},
...
Replace tabs with spaces in vim
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393
IIRC, something like:
set tabstop=2 shiftwidth=2 expandtab
should do the trick. If you alre...
PyCharm shows unresolved references error for valid code
...Dmitry Trofimov
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3
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Invalid syntax when using “print”? [duplicate]
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232
That is because in Python 3, they have replaced the print statement with the print function.
T...
How to split (chunk) a Ruby array into parts of X elements? [duplicate]
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341
Take a look at Enumerable#each_slice:
foo.each_slice(3).to_a
#=> [["1", "2", "3"], ["4", "...
Remove and Replace Printed items [duplicate]
...
3 Answers
3
Active
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How to save a list as numpy array in python?
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163
First of all, I'd recommend you to go through NumPy's Quickstart tutorial, which will probably ...
Python way of printing: with 'format' or percent form? [duplicate]
...
Use the format method, especially if you're concerned about Python 3 and the future. From the documentation:
The formatting operations described here are modelled on C's printf()
syntax. They only support formatting of certain builtin types. The
use of a binary operator mean...
What is the inverse function of zip in python? [duplicate]
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349
lst1, lst2 = zip(*zipped_list)
should give you the unzipped list.
*zipped_list unpacks the ...
Creating NSData from NSString in Swift
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361
In Swift 3
let data = string.data(using: .utf8)
In Swift 2 (or if you already have a NSSt...