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'and' (boolean) vs '&' (bitwise) - Why difference in behavior with lists vs numpy arrays?
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and tests whether both expressions are logically True while & (when used with True/False values) tests if both are True.
In Python, empty built-in objects are typically treated as logically False while non-empty built-ins are logically True. This facilitates the c...
What is the difference between #import and #include in Objective-C?
... decent header files protect themselves against this anyway, so it's not really that much of a benefit.
Basically, it's up to you to decide which you want to use. I tend to #import headers for Objective-C things (like class definitions and such) and #include standard C stuff that I need. For exampl...
Why do Java programmers like to name a variable “clazz”? [closed]
...nvention ? I think 'clazz' is not even an English word , has no meaning at all , how can so many programmers name a wrong name coincidentally ?
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what is the best way to convert a json formatted key value pair to ruby hash with symbol as key?
... string key
}
}
Method 1: JSON.parse - symbolizes all keys recursively => Does not preserve original mix
JSON.parse( h.to_json, {:symbolize_names => true} )
=> { :youtube => { :search=> "daffy", :history => ["goofy", "mickey"] } }
Method 2: ActiveSup...
How to check if a string contains only digits in Java [duplicate]
In Java for String class there is a method called matches, how to use this method to check if my string is having only digits using regular expression. I tried with below examples, but both of them returned me false as result.
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PHP - Debugging Curl
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You can enable the CURLOPT_VERBOSE option:
curl_setopt($curlhandle, CURLOPT_VERBOSE, true);
When CURLOPT_VERBOSE is set, output is written to STDERR or the file specified using CURLOPT_STDERR. The output is very informative.
You can also use tcpdu...
Avoid browser popup blockers
...m javascript that is not invoked by direct user action. That is, you can call window.open in response to a button click without getting hit by the popup blocker, but if you put the same code in a timer event it will be blocked. Depth of call chain is also a factor - some older browsers only look a...
while (1) vs. while(True) — Why is there a difference (in python 2 bytecode)?
...me byte code for while(True): pass and while(1): pass , but this is actually not the case in python2.7.
3 Answers
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Assign multiple columns using := in data.table, by group
...t(dim(get(objectName))),by=objectName]. Trouble is that as.list has call overhead and also copies the small vector. If efficiency is a problem as number of groups rises then please let us know.
– Matt Dowle
May 21 '14 at 11:49
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Find element's index in pandas Series
... The trouble here is it assumes the element being searched for is actually in the list. It's a bummer pandas doesn't seem to have a built in find operation.
– jxramos
Aug 23 '17 at 17:16
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