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Operator overloading : member function vs. non-member function?
... as member function is asymmetric because it can have only one parameter and the other parameter passed automatically is the this pointer. So no standard exists to compare them. On the other hand, overloaded operator declared as a friend is symmetric because we pass two arguments of the same...
Get ffmpeg information in friendly way
...t information you want it to display (with the -show_format, -show_packets and -show_streams options) or it'll just give you blank output (like you mention in one of your comments).
For example, ffprobe -v quiet -print_format json -show_format -show_streams somefile.asf would yield something like t...
How to generate random SHA1 hash to use as ID in node.js?
...o create a HMAC-SHA1 hash?
I'd create a hash of the current timestamp + a random number to ensure hash uniqueness:
var current_date = (new Date()).valueOf().toString();
var random = Math.random().toString();
crypto.createHash('sha1').update(current_date + random).digest('hex');
...
SQL Query Where Field DOES NOT Contain $x
... the given string, it can use indices (if there is an index on that field) and be reasonably fast:
-- Finds all rows where a does not start with "text"
SELECT * FROM x WHERE x.a NOT LIKE 'text%';
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Requests — how to tell if you're getting a 404
I'm using the Requests library and accessing a website to gather data from it with the following code:
1 Answer
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How do I catch a numpy warning like it's an exception (not just for testing)?
...rr(all='warn'), which will transform the printed warning in a real warning and you'll be able to use the above solution to localize this change in behaviour.
Once you actually have a warning, you can use the warnings module to control how the warnings should be treated:
>>> import warnin...
Is there a Newline constant defined in Java like Environment.Newline in C#?
...
As of Java 7 (and Android API level 19):
System.lineSeparator()
Documentation: Java Platform SE 7
For older versions of Java, use:
System.getProperty("line.separator");
See https://java.sun.com/docs/books/tutorial/essential/enviro...
SQLAlchemy: What's the difference between flush() and commit()?
What the difference is between flush() and commit() in SQLAlchemy?
5 Answers
5
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Is C++14 adding new keywords to C++?
The C++ Standards Committee tends to shy away from adding new keywords to the language, yet with C++11 that was not the case. Some examples:
...
What does gcc's ffast-math actually do?
I understand gcc's --ffast-math flag can greatly increase speed for float ops, and goes outside of IEEE standards, but I can't seem to find information on what is really happening when it's on. Can anyone please explain some of the details and maybe give a clear example of how something would chan...