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php is null or empty?
...===.
When use ==, as you did, PHP treats NULL, false, 0, the empty string, and empty arrays as equal.
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What is the difference between NaN and None?
I am reading two columns of a csv file using pandas readcsv() and then assigning the values to a dictionary. The columns contain strings of numbers and letters. Occasionally there are cases where a cell is empty. In my opinion, the value read to that dictionary entry should be None but instead ...
Positioning element at center of screen
...creen irrespective of screen size. In other words, the space left on 'top' and 'bottom' should be equal and space left on 'right' and 'left' sides should be equal. I would like to accomplish this with only CSS.
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Should we use Nexus or Artifactory for a Maven Repo?
...odules). We have been storing our external dependencies in source control, and using that to update a local repo.
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Find a pair of elements from an array whose sum equals a given number
Given array of n integers and given a number X, find all the unique pairs of elements (a,b), whose summation is equal to X.
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What is the effect of extern “C” in C++?
...then link to using the C name.
Since C++ has overloading of function names and C does not, the C++ compiler cannot just use the function name as a unique id to link to, so it mangles the name by adding information about the arguments. A C compiler does not need to mangle the name since you can not ...
Can I replace groups in Java regex?
I have this code, and I want to know, if I can replace only groups (not all pattern) in Java regex.
Code:
7 Answers
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Are duplicate keys allowed in the definition of binary search trees?
I'm trying to find the definition of a binary search tree and I keep finding different definitions everywhere.
12 Answers
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comparing sbt and Gradle [closed]
I am diving into Scala and noticed sbt. I have been quite happy with Gradle in java/groovy projects, and I know there's a scala plugin for Gradle.
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In PHP, what is a closure and why does it use the “use” identifier?
I'm checking out some PHP 5.3.0 features and ran across some code on the site that looks quite funny:
6 Answers
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