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Why is f(i = -1, i = -1) undefined behavior?
I was reading about order of evaluation violations , and they give an example that puzzles me.
11 Answers
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Check free disk space for current partition in bash
I am writing an installer in bash. The user will go to the target directory and runs the install script, so the first action should be to check that there is enough space. I know that df will report all file systems, but I was wondering if there was a way to get the free space just for the partition...
Checking images for similarity with OpenCV
Does OpenCV support the comparison of two images, returning some value (maybe a percentage) that indicates how similar these images are? E.g. 100% would be returned if the same image was passed twice, 0% would be returned if the images were totally different.
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How to get the type of T from a member of a generic class or method?
Let say I have a generic member in a class or method, so:
16 Answers
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Short description of the scoping rules?
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Actually, a concise rule for Python Scope resolution, from Learning Python, 3rd. Ed.. (These rules are specific to variable names, not attributes. If you reference it without a period, these rules apply.)
LEGB Rule
Local — Names assigned in any w...
How does the getView() method work when creating your own custom adapter?
...ews, when a View is scrolled so that is no longer visible, it can be used for one of the new Views appearing. This reused View is the convertView. If this is null it means that there is no recycled View and we have to create a new one, otherwise we should use it to avoid creating a new.
3: The pare...
Java regular expression OR operator
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You can just use the pipe on its own:
"string1|string2"
for example:
String s = "string1, string2, string3";
System.out.println(s.replaceAll("string1|string2", "blah"));
Output:
blah, blah, string3
The main reason to use parentheses is to limit the scope of the alternatives:
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Can I browse other people's (Apple) bug reports? [closed]
When I log into the Bug Reporter tool that Apple has, I can only see my bugs. I normally like to search the system to see if other people have filed a bug before posting, but I can't see any way to do this. I can only see my bugs, and post new bugs, but I can't see any way to browse or search the wh...
Rename specific column(s) in pandas
...a dataframe called data . How would I rename the only one column header? For example gdp to log(gdp) ?
5 Answers
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JavaScript variables declare outside or inside loop?
In AS3 I believe you should initialise all variables outside loops for increased performance. Is this the case with JavaScript as well? Which is better / faster / best-practice?
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