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Mongodb Explain for Aggregation framework
...ther manipulation will be in-memory (possibly using temporary files if the allowDiskUse option is set).
Optimizing pipelines
In general, you can optimize aggregation pipelines by:
Starting a pipeline with a $match stage to restrict processing to relevant documents.
Ensuring the initial $match / ...
Conditional HTML Attributes using Razor MVC3
...s" />
If strCSSClass is null then the class attribute won't render at all.
SSSHHH...don't tell. :)
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Performance surprise with “as” and nullable types
...lable types, and I'm adding a section about using the "as" operator, which allows you to write:
10 Answers
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Can I change the checkbox size using CSS?
...ers no solutions in many cases (no solution to firefox on xp? no chrome at all?), is outdated and only contains a link and a comment of not much value.
– nurettin
Feb 13 '13 at 15:34
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Can dplyr package be used for conditional mutating?
...and the conditions (except for the default value of NA at the end) are mutually exclusive, as is the case in the question, then we can use an arithmetic expression such that each term is multiplied by the desired result using na_if at the end to replace 0 with NA.
df %>%
mutate(g = 2 * (a == 2 ...
Comparing two dictionaries and checking how many (key, value) pairs are equal
... will fail on values that aren't hashable.
– Tim Tisdall
Apr 10 '17 at 13:51
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How to get the last N rows of a pandas DataFrame?
...000/svg\"\u003e\u003cpath d=\"M46.1709 9.17788C46.1709 8.26454 46.2665 7.94324 47.1084 7.58816C47.4091 7.46349 47.7169 7.36433 48.0099 7.26993C48.9099 6.97997 49.672 6.73443 49.672 5.93063C49.672 5.22043 48.9832 4.61182 48.1414 4.61182C47.4335 4.61182 46.7256 4.91628 46.0943 5.50789C45.7307 4.9328 4...
fork() branches more than expected?
...000/svg\"\u003e\u003cpath d=\"M46.1709 9.17788C46.1709 8.26454 46.2665 7.94324 47.1084 7.58816C47.4091 7.46349 47.7169 7.36433 48.0099 7.26993C48.9099 6.97997 49.672 6.73443 49.672 5.93063C49.672 5.22043 48.9832 4.61182 48.1414 4.61182C47.4335 4.61182 46.7256 4.91628 46.0943 5.50789C45.7307 4.9328 4...
How to print instances of a class using print()?
... anyway...)
– kender
Oct 8 '09 at 5:32
@kender - I didn't know about it, but in retrospect it makes perfect sense give...
How do I write data into CSV format as string (not file)?
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I found the answers, all in all, a bit confusing. For Python 2, this usage worked for me:
import csv, io
def csv2string(data):
si = io.BytesIO()
cw = csv.writer(si)
cw.writerow(data)
return si.getvalue().strip('\r\n')
data=[1,2...