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Reshaping data.frame from wide to long format
...s melt/cast. Here is a solution with reshape, assuming your data frame is called d:
reshape(d,
direction = "long",
varying = list(names(d)[3:7]),
v.names = "Value",
idvar = c("Code", "Country"),
timevar = "Year",
times = 1950:1954)
...
What is a higher kinded type in Scala?
...pply to value arguments to "construct" a value.
Value constructors are usually called "functions" or "methods". These "constructors" are also said to be "polymorphic" (because they can be used to construct "stuff" of varying "shape"), or "abstractions" (since they abstract over what varies between ...
Simple Digit Recognition OCR in OpenCV-Python
...stand some of the features at end)
2) Since I knew, without understanding all those features, it is difficult to do that method. I tried some other papers, but all were a little difficult for a beginner.
So I just decided to take all the pixel values as my features. (I was not worried about accura...
PHP function to make slug (URL string)
...aprint") will return "EFI" and leak a warning.
– Kendall Hopkins
Feb 14 '12 at 2:12
2
@Maerlyn an...
(grep) Regex to match non-ASCII characters?
...y with lots of files. Some of them have non-ASCII characters, but they are all valid UTF-8 . One program has a bug that prevents it working with non-ASCII filenames, and I have to find out how many are affected. I was going to do this with find and then do a grep to print the non-ASCII characte...
Convert integer into its character equivalent, where 0 => a, 1 => b, etc
...his edit? I think it makes it harder to read. Now I have to scroll horizontally to read the code.
– z0r
May 11 '17 at 1:23
...
How to encrypt/decrypt data in php?
... $length = $size - strlen($data) % $size;
return $data . str_repeat(chr($length), $length);
}
$name = 'Jack';
$enc_name = openssl_encrypt(
pkcs7_pad($name, 16), // padded data
'AES-256-CBC', // cipher and mode
$encryption_key, // secret key
0, /...
How do I match any character across multiple lines in a regular expression?
...P it is:
/(.*)<FooBar>/s
The s at the end causes the dot to match all characters including newlines.
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How to avoid variable substitution in Oracle SQL Developer with 'trinidad & tobago'
...
My question was how this could be done without using chr(38).
– Janek Bogucki
Oct 12 '18 at 17:29
...
Remove multiple whitespaces
I'm getting $row['message'] from a MySQL database and I need to remove all whitespace like \n \t and so on.
15 Answer...