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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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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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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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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 / ...
Split data frame string column into multiple columns
...N", "N")'
– maycca
May 22 '18 at 19:32
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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 ...
What does the JSLint error 'body of a for in should be wrapped in an if statement' mean?
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First of all, never use a for in loop to enumerate over an array. Never. Use good old for(var i = 0; i<arr.length; i++).
The reason behind this is the following: each object in JavaScript has a special field called prototype. Ever...
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...
jQuery scroll() detect when user stops scrolling
...vent handler function for one or more events to the selected elements and calls the handler function if the event was not triggered for a given interval. This is useful if you want to fire a callback only after a delay, like the resize event, or such.
It is important to check the github-repo for up...
Make Bootstrap Popover Appear/Disappear on Hover instead of Click
...r data-attributes ? Even if I use data-attributes, I still would have to call $("#popover").popover(); from my JavaScript.
– Bailey
Jan 3 '18 at 7:58
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