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Include all existing fields and add new fields to document
...s the new fields.
db.collection.aggregate([
{ "$addFields": { "custom_field": "$obj.obj_field1" } }
])
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Cleaner way to update nested structures
...ss, and an address in a person:
val addressZipCodeLens = Lens(
get = (_: Address).zipCode,
set = (addr: Address, zipCode: Int) => addr.copy(zipCode = zipCode))
val personAddressLens = Lens(
get = (_: Person).address,
set = (p: Person, addr: Address) => p.copy(address = addr)...
How to convert a string to utf-8 in Python
...
In Python 2
>>> plain_string = "Hi!"
>>> unicode_string = u"Hi!"
>>> type(plain_string), type(unicode_string)
(<type 'str'>, <type 'unicode'>)
^ This is the difference between a byte string (plain_string) and a unic...
Can you find all classes in a package using reflection?
...0, file.getName().length() - 6)));
}
}
return classes;
}
__________
1 This method was taken originally from http://snippets.dzone.com/posts/show/4831, which was archived by the Internet Archive, as linked to now. The snippet is also available at https://dzone.com/articles/get-all-c...
Convert a row of a data frame to vector
...u have to be careful if your row contains a factor. Here is an example:
df_1 = data.frame(V1 = factor(11:15),
V2 = 21:25)
df_1[1,] %>% as.numeric() # you expect 11 21 but it returns
[1] 1 21
Here is another example (by default data.frame() converts characters to factors)
d...
How to get last items of a list in Python?
...
a negative index will count from the end of the list, so:
num_list[-9:]
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How can I check if a string represents an int, without using try/except?
...0' format, which is similar to int casting in this sense.
edit:
def check_int(s):
if s[0] in ('-', '+'):
return s[1:].isdigit()
return s.isdigit()
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Return a value if no rows are found in Microsoft tSQL
... but ideally it should return multiple values. select case when count(QTIB_REQ_)<1 then 0 else QTIB_REQ_ end from qb_requisitions_all where QTIB_REQ_ IN ($Req_disabled_WA) and CLIENT___BENCH___NON_BILLABLE NOT IN ( 'Non Billable', 'Non-Billable', 'NonBillable', 'Bench', 'Bench - SC Cleared S...
how to return index of a sorted list? [duplicate]
...ray([2,3,1,4,5])
>>> vals
array([2, 3, 1, 4, 5])
>>> sort_index = numpy.argsort(vals)
>>> sort_index
array([2, 0, 1, 3, 4])
If not available, taken from this question, this is the fastest method:
>>> vals = [2,3,1,4,5]
>>> sorted(range(len(vals)), key=...
How to call C from Swift?
... frame = CGRect(x: 10, y: 10, width: 100, height: 100)
import Darwin
for _ in 1..10 {
println(rand() % 100)
}
See Interacting with Objective-C APIs in the docs.
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