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Why use argparse rather than optparse?
I noticed that the Python 2.7 documentation includes yet another command-line parsing module. In addition to getopt and optparse we now have argparse .
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When to use a key/value store such as Redis instead/along side of a SQL database?
I have read great things about key/value stores such as Redis but I can't seem to figure out when it's time to use it in an application.
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Remove columns from dataframe where ALL values are NA
...able(bd)
system.time({df1 <- bd[,colSums(is.na(bd) < nrow(bd))]})
# error -- can't allocate vector of size ...
system.time({df2 <- bd[, !apply(is.na(bd), 2, all)]})
# error -- can't allocate vector of size ...
system.time({df3 <- Filter(function(x)!all(is.na(x)), bd)})
## user system e...
Can't connect Nexus 4 to adb: unauthorized
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I think it has an error when the device tries to display the screen asking for permission, so it does not appear.
This works for me (commands are given in the adb shell):
rm /data/misc/adb/adb_keys;
I sent the public key (adbkey.pub in ~/.a...
What is the memory consumption of an object in Java?
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Datatables - Search Box outside datatable
...red to be able to call .search on it (if will throw a "function undefined" error otherwise). See: datatables.net/faqs/#api
– Lionel
Mar 30 '15 at 7:28
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Why does Eclipse automatically add appcompat v7 library support whenever I create a new project?
...quit patching and patching and patching, all these bunch of supportLibrary errors and versions are driving us nuts.
– Josh
Jul 20 '15 at 9:44
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What does the exclamation mark do before the function?
...ight be tempted to try this:
function () {}()
but it results in a SyntaxError.
Using the ! operator before the function causes it to be treated as an expression, so we can call it:
!function () {}()
This will also return the boolean opposite of the return value of the function, in this case t...
Python import csv to list
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This does not work in Python 3.x : "csv.Error: iterator should return strings, not bytes (did you open the file in text mode?)" See below for the answer that works in Python 3.x
– Gilbert
May 30 '16 at 18:12
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I change the capitalization of a directory and Git doesn't seem to pick up on it
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That fatal error means you do not have a GIT repository at that location. git commands only work in directories with GIT repositories.
– David Manpearl
Sep 8 '15 at 18:43
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