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'and' (boolean) vs '&' (bitwise) - Why difference in behavior with lists vs numpy arrays?
...e 1:
This is how the and operator works.
x and y =>
if x is false, then x, else y
So in other words, since mylist1 is not False, the result of the expression is mylist2. (Only empty lists evaluate to False.)
Example 2:
The & operator is for a bitwise and, as you mention. Bitwise opera...
Why is the .bss segment required?
...tored in RAM, but init_value is stored in ROM. If it had been one segment, then the ROM had to be filled up with a lot of zeroes, increasing ROM size significantly.
RAM-based executables work similarly, though of course they have no true ROM.
Also, memset is likely some very efficient inline assem...
What is WEB-INF used for in a Java EE web application?
...s, plain text files, script files) in your application root directory. But then, people can access them directly from their browser, instead of their requests being processed by some logic provided by your application. So, to prevent your resources being directly accessed like that, you can put them...
When should I use a struct rather than a class in C#?
.... If a structure represents a single entity [as with Decimal or DateTime], then if it would not abide by the other three rules, it should be replaced by a class. If a structure holds a fixed collection of variables, each of which may hold any value that would be valid for its type [e.g. Rectangle], ...
Does Java casting introduce overhead? Why?
...Again this is analogous to reading a method pointer for a virtual method.
Then the read value just needs a comparison to the expected static type of the cast. Depending upon instruction set architecture, another instruction will need to branch (or fault) on an incorrect branch. ISAs such as 32-bit ...
What's the difference between --general-numeric-sort and --numeric-sort options in gnu sort
...TE=us_EN.UTF-8 not ignore).
So if you are sorting arbitrary alphanumeric then you probably don't want -g. If you really need scientific notation comparison with -g, then you probably want to extract alphabet and
numeric data and do comparison separately.
If you only need ordinary number(e.g. 1...
Using emit vs calling a signal as if it's a regular function in Qt
...t psuedo-keyword-comment was to make clear that a signal is being invoked, then a naming convention could do the same, with no mystery and with similar benefits. The naming convention couldn't be enforced by Qt (actually, moc could enforce it - but I'm not advocating that either), but Qt can't enfor...
Git Cherry-pick vs Merge Workflow
...rge number of conflicts do I back up and re-run the merge piecemeal. Even then I do it in large chunks. As a very real example I had a colleague who had 3 months worth of changes to merge, and got some 9000 conflicts in 250000 line code-base. What we did to fix is do the merge one month's worth a...
Please explain some of Paul Graham's points on Lisp
..." the interpreter first creates a floating point object with value 82.4. Then it calls a string constructor which then returns a string with value '82.4'. The 'a' on the left hand side is merely a label for that string object. The original floating point object was garbage collected because ther...
FixedThreadPool vs CachedThreadPool: the lesser of two evils
...ges when you do in fact want to work with a fixed number of threads, since then you can submit any number of tasks to the executor service while knowing that the number of threads will be maintained at the level you specified. If you explicitly want to grow the number of threads, then this is not t...