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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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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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Seeking clarification on apparent contradictions regarding weakly typed languages
I think I understand strong typing , but every time I look for examples for what is weak typing I end up finding examples of programming languages that simply coerce/convert types automatically.
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Iterating over every two elements in a list
...+ y)
In Python 3, you can replace izip with the built-in zip() function, and drop the import.
All credit to martineau for his answer to my question, I have found this to be very efficient as it only iterates once over the list and does not create any unnecessary lists in the process.
N.B: This ...
How to tell Xcode where my info.plist and .pch files are
I renamed my project and it's files and now Xcode is still looking for the old info.plist file. Where do I set the locations of the .plist and .pch files that it needs.
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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 ...
What are the use cases for selecting CHAR over VARCHAR in SQL?
...R(10) = 10 bytes (4 bytes of waste)
The bottom line is CHAR can be faster and more space-efficient for data of relatively the same length (within two characters length difference).
Note: Microsoft SQL has 2 bytes of overhead for a VARCHAR. This may vary from DB to DB, but generally, there is at lea...
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.
12 Answer...
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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