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How do I replace NA values with zeros in an R dataframe?
...ent in @gsk3 answer. A simple example:
> m <- matrix(sample(c(NA, 1:10), 100, replace = TRUE), 10)
> d <- as.data.frame(m)
V1 V2 V3 V4 V5 V6 V7 V8 V9 V10
1 4 3 NA 3 7 6 6 10 6 5
2 9 8 9 5 10 NA 2 1 7 2
3 1 1 6 3 6 NA 1 4 1 6
4 NA 4 NA 7 10 2 NA 4 ...
Iterate keys in a C++ map
...
+1: Finally, someone who read the "not the pairs" bit! Cheers, this has saved me time digging through the spec!
– Mark K Cowan
Aug 25 '14 at 12:43
1
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Logical operators (“and”, “or”) in DOS batch
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Just to improve your answer a bit... you don't need to explicitly nest the "if" statements... you can just "chain" them, as Dave Jarvis demonstrates below
– JoelFan
Jan 28 '10 at 14:44
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Some questions about Automatic Reference Counting in iOS5 SDK
...r flag. ARC is supported in
Xcode 4.2 for Mac OS X v10.6 and v10.7
(64-bit applications) and for iOS 4
and iOS 5. (Weak references are not
supported in Mac OS X v10.6 and iOS
4). There is no ARC support in Xcode
4.1.
-
If I develop a new app for iOS 5 using
ARC, will I need t...
Best way to convert string to bytes in Python 3?
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@hmijail you win nothing by explicitly typing the default argument values - more keystrokes, larger code and it is slower too.
– Antti Haapala
Jul 25 at 7:16
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How do you sign a Certificate Signing Request with your Certification Authority?
...##########################################################
[ req ]
default_bits = 4096
default_keyfile = cakey.pem
distinguished_name = ca_distinguished_name
x509_extensions = ca_extensions
string_mask = utf8only
###################################################################...
Determine if 2 lists have the same elements, regardless of order? [duplicate]
...ue, you can also convert to sets (same asymptotic runtime, may be a little bit faster in practice):
set(x) == set(y)
If the elements are not hashable, but sortable, another alternative (runtime in O(n log n)) is
sorted(x) == sorted(y)
If the elements are neither hashable nor sortable you can u...
C++ project organisation (with gtest, cmake and doxygen)
...ng a simple vector class in C++. However I would like to get in to good habits from the start rather than trying to modify my workflow later on.
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“Register” an .exe so you can run it from any command line in Windows
How can you make a .exe file accessible from any location in the Windows command window? Is there some registry entry that has to be entered?
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How to correctly display .csv files within Excel 2013?
...pen the CSV file with a decent text editor like Notepad++ and add the following text in the first line:
sep=,
Now open it with excel again.
This will set the separator as a comma, or you can change it to whatever you need.
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