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Determine the number of NA values in a column
... In counting amount of arbitrary value, other than NA is writing a boolean function is.value and then using sum(is.value(df$col)) the way to go or is there a more concise direct syntax for this?
– user3274289
Jun 4 '14 at 2:11
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Getting the first index of an object
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Just for fun this works in JS 1.8.5
var obj = {a: 1, b: 2, c: 3};
Object.keys(obj)[0]; // "a"
This matches the same order that you would see doing
for (o in obj) { ... }
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Working Soap client example
...@gmail.com</example:email>
<example:LicenseKey>123</example:LicenseKey>
</example:VerifyEmail>
</SOAP-ENV:Body>
</SOAP-ENV:Envelope>
*/
// SOAP Body
SOAPBody soapBody = envelope.getBody();
SOAPElement soapB...
How do I extract text that lies between parentheses (round brackets)?
...e (sales)", @"\(([^)]*)\)").Groups[1].Value
As a response to the (very funny) comment, here's the same Regex with some explanation:
\( # Escaped parenthesis, means "starts with a '(' character"
( # Parentheses in a regex mean "put (capture) the stuff
# ...
How to enable external request in IIS Express?
...why I wrote a simple proxy utility specifically for this kind of scenario: https://github.com/icflorescu/iisexpress-proxy.
Using the IIS Express Proxy, it all becomes quite simple – no need to “netsh http add urlacl url=vaidesg:8080/ user=everyone” or to mess up with your “applicationhost.c...
Remove the last line from a file in Bash
...or handling and some other features, you can use the poptail command here:
https://github.com/donm/evenmoreutils
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move_uploaded_file gives “failed to open stream: Permission denied” error
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ps aux | grep https doesn't return web server owner name. This does : ps aux | grep -E '[a]pache|[h]ttpd|[_]www|[w]ww-data|[n]ginx' | grep -v root | head -1 | cut -d\ -f1 Fron Symfony doc.
– David Jacquel
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What's the difference between interface and @interface in java?
...eUploader: {
brandingHtml: "Powered by \u003ca href=\"https://imgur.com/\"\u003e\u003csvg class=\"svg-icon\" width=\"50\" height=\"18\" viewBox=\"0 0 50 18\" fill=\"none\" xmlns=\"http://www.w3.org/2000/svg\"\u003e\u003cpath d=\"M46.1709 9.17788C46.1709 8.26454 46.2665 7.94324 4...
How to check whether a file is empty or not?
...size() and stat() will throw an exception if the file does not exist. This function will return True/False without throwing (simpler but less robust):
import os
def is_non_zero_file(fpath):
return os.path.isfile(fpath) and os.path.getsize(fpath) > 0
...
What do the plus and minus signs mean in Objective-C next to a method?
...on of this from Apple is here, under the 'Methods and Messaging' section:
https://developer.apple.com/library/mac/referencelibrary/GettingStarted/RoadMapOSX/books/WriteObjective-CCode/WriteObjective-CCode/WriteObjective-CCode.html
In brief:
+ means 'class method'
(method can be called without an...