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How do I get SUM function in MySQL to return '0' if no values are found?
Say I have a simple function in MySQL:
4 Answers
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Get pandas.read_csv to read empty values as empty string instead of nan
I'm using the pandas library to read in some CSV data. In my data, certain columns contain strings. The string "nan" is a possible value, as is an empty string. I managed to get pandas to read "nan" as a string, but I can't figure out how to get it not to read an empty value as NaN. Here's sam...
Left align and right align within div in Bootstrap
What are some of the common ways to left align some text and right align some other text within a div container in bootstrap?
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How to pull request a wiki page on GitHub?
...Hub that isn't open for editing. Then I forked the project, edited it on "my end" and tried to do a pull request. It turns out, the wiki isn't in the project, and there isn't a way to commit changes to it.
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What does 'wb' mean in this code, using Python?
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File mode, write and binary. Since you are writing a .jpg file, it looks fine.
But if you supposed to read that jpg file you need to use 'rb'
More info
On Windows, 'b' appended to the mode
opens the file in binary mode, s...
CPU Privilege Rings: Why rings 1 and 2 aren't used?
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As a hobbyist operating system writer, I found that because paging (a major part of the modern protection model) only has a concept of privileged (ring 0,1,2) and unprivileged, the benefit to rings 1 and 2 were diminished greatly.
The intent by Intel in...
Case insensitive access for generic dictionary
I have an application that use managed dlls. One of those dlls return a generic dictionary:
3 Answers
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Following git-flow how should you handle a hotfix of an earlier release?
If you try to follow the git-flow branching model, documented here and with tools here , how should you handle this situation:
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sed: print only matching group
I want to grab the last two numbers (one int, one float; followed by optional whitespace) and print only them.
5 Answers
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NULL vs nil in Objective-C
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nil should only be used in place of an id, what we Java and C++ programmers would think of as a pointer to an object. Use NULL for non-object pointers.
Look at the declaration of that method:
- (void)observeValueForKeyPath:(NSString *)keyPath ofObject:(id)object
change:(NSDictionary *)cha...