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How to avoid warning when introducing NAs by coercion
... na = x %in% na.strings
x[na] = 0
x = as.numeric(x)
x[na] = NA_real_
x
}
as.num(c("1", "2", "X"), na.strings="X")
#[1] 1 2 NA
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Streaming Audio from A URL in Android using MediaPlayer?
...et rejected b'coz I have used Vitamio 4.x version
– Pallavi
Dec 22 '16 at 14:31
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Extract a dplyr tbl column as a vector
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This seems the most versatile method as it works identically with vectors and data.frames, i.e. it enables functions to be more agnostic.
– geotheory
Mar 14 '17 at 10:03
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Which is the fastest algorithm to find prime numbers?
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Actually I don't think primegen is the fastest, or even the second-fastest; yafu and primesieve are both faster in general, I think, and certainly over 2^32. Both are (modified) sieves of Eratosthenes rather than the Atkin-Berns...
UINavigationController without navigation bar?
...Hidden box instead of using code. I've recently been on a kick of creating all my interfaces entirely programmatically without .xib files, so went straight to that for my answer.
– Ashwin
Apr 24 '11 at 3:45
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Android SDK on a 64-bit linux machine
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Yes, it is. You need to install the ia32 libraries. Check out the Ubuntu Linux troubleshooting section.
apt-get install ia32-libs
apt-get install sun-java6-jdk
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Ruby - test for array
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Type checking is for Java. Go ahead and just call count on the variable. Write unit tests to make sure the method works as expected.
– user132447
Mar 21 '12 at 14:55
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How do I URL encode a string
...om/message/15674#15674
http://simonwoodside.com/weblog/2009/4/22/how_to_really_url_encode/
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Convert char to int in C and C++
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Well, in ASCII code, the numbers (digits) start from 48. All you need to do is:
int x = (int)character - 48;
Or, since the character '0' has the ASCII code of 48, you can just write:
int x = character - '0'; // The (int) cast is not necessary.
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Attempt to set a non-property-list object as an NSUserDefaults
...ray to any method that expects an NSArray. Keep in mind that the array actually stored in NSUserDefaults will be immutable when you read it back.
– rmaddy
Nov 1 '13 at 4:42
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