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How to randomize (or permute) a dataframe rowwise and columnwise?

...] 1 0 0 1 0 [4,] 0 0 1 0 1 To explain the call: out <- permatswap(mat, times = 99, burnin = 20000, thin = 500, mtype = "prab") times is the number of randomised matrices you want, here 99 burnin is the number of swaps made before we start taking random samples....
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How to check if hex color is “too black”?

... You have to extract the three RGB components individually, and then use a standard formula to convert the resulting RGB values into their perceived brightness. Assuming a six character colour: var c = c.substring(1); // strip # var rgb = parseInt(c, 16); // convert rrg...
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Xcode stuck at “Your application is being uploaded”

... just keep your head cool and check this first method: Check if your firewall protection is off. If not then turn it off. It maybe blocking you to connect your computer with iTunes Store. Try a different internet connection. The purpose for trying a different internet connection is that your curre...
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How to get device make and model on iOS?

... if I have an iPhone 3GS vs. and iPhone 4 vs. an iPhone 4S (in actuality, all I really want to do is determine if I have a 3G or not, because I'm doing fairly graphics intensive stuff) . ...
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What is the difference between UTF-8 and ISO-8859-1?

...e points of the Unicode character set, whereas UTF-8 can be used to encode all code points. At physical encoding level, only codepoints 0 - 127 get encoded identically; code points 128 - 255 differ by becoming 2-byte sequence with UTF-8 whereas they are single bytes with Latin-1. ...
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What is the email subject length limit?

How many characters are allowed to be in the subject line of Internet email? I had a scan of The RFC for email but could not see specifically how long it was allowed to be. I have a colleague that wants to programmatically validate for it. ...
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leading zeros in rails

...using a given padding character. str.rjust(integer, padstr=' ') → new_str If integer is greater than the length of str, returns a new String of length integer with str right justified and padded with padstr; otherwise, returns str. some_int = 5 some_int.to_s.rjust(2, '0') # => '05' ...
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Check for internet connection availability in Swift

...unc isConnectedToNetwork() -> Bool { var zeroAddress = sockaddr_in(sin_len: 0, sin_family: 0, sin_port: 0, sin_addr: in_addr(s_addr: 0), sin_zero: (0, 0, 0, 0, 0, 0, 0, 0)) zeroAddress.sin_len = UInt8(sizeofValue(zeroAddress)) zeroAddress.sin_family = sa_family_t(AF_INET)...
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docker error: /var/run/docker.sock: no such file or directory

...ker file that runs builds an image and run the container. I am on mac, installed boot2docker and have the DOCKER_HOST env set up. ...
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How to avoid “Permission denied” when using pip with virtualenv

...ed Oct 19 '13 at 23:02 sebastian_oesebastian_oe 6,63822 gold badges1515 silver badges2020 bronze badges ...