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Change column type from string to float in Pandas
...arly useful when you want to convert your entire DataFrame, but don't not know which of our columns can be converted reliably to a numeric type. In that case just write:
df.apply(pd.to_numeric, errors='ignore')
The function will be applied to each column of the DataFrame. Columns that can be conver...
What are the disadvantages of using persistent connection in PDO
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I know a big website that has been using persistent connections for nearly a decade now. The trick is using a layer above the DB extension, and having it remember the things that need to be cleaned up by using register_shutdown_...
How do I find the duplicates in a list and create another list with them?
...q):
seen = set()
seen_add = seen.add
# adds all elements it doesn't know yet to seen and all other to seen_twice
seen_twice = set( x for x in seq if x in seen or seen_add(x) )
# turn the set into a list (as requested)
return list( seen_twice )
a = [1,2,3,2,1,5,6,5,5,5]
list_duplicates(a...
Does PowerShell support constants?
...the Set-Variable cmdlet:
Set-Variable myvar -option Constant -value 100
Now $myvar has a constant value of 100 and cannot be modified.
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callback to handle completion of pipe
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The 'end' event is now 'finish' Pipe events: nodejs.org/api/stream.html#stream_event_finish
– Pier-Luc Gendreau
Apr 16 '14 at 14:44
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Good MapReduce examples [closed]
... -> (C D)
(C D) -> (A B E)
(C E) -> (B D)
(D E) -> (B C)
Now when D visits B's profile, we can quickly look up (B D) and see
that they have three friends in common, (A C E).
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How to use Git properly with Xcode?
...Cocoa PList file, which is older, and defined a lot earlier than JSON, and now deprecated by Apple. (but they are still using it in some places) The mention about the file in the book is completely wrong. I removed down vote because you mentioned it explicitly.
– eonil
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Are Databases and Functional Programming at odds?
I've been a web developer for some time now, and have recently started learning some functional programming. Like others, I've had some significant trouble apply many of these concepts to my professional work. For me, the primary reason for this is I see a conflict between between FP's goal of rem...
.NET NewtonSoft JSON deserialize map to a different property name
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@NateCook can you show me a sample? i need it badly right now
– deadManN
Jul 24 '16 at 13:14
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What does middleware and app.use actually mean in Expressjs?
... a late answer to add something not mentioned in the previous answers.
By now it should be clear that middleware is/are function(s) run between the client request and the server answer. The most common middleware functionality needed are error managing, database interaction, getting info from stati...