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'and' (boolean) vs '&' (bitwise) - Why difference in behavior with lists vs numpy arrays?
...ting. I hadn't thought of it that way. I was thinking of {a,b} as being an ordered pair (even though you used set brackets), because I was thinking you meant to try: (True, True), (True, False), (False, True), and (False, False), so I thought (True, True) is not a subset of {True, False}, but I can ...
REST vs JSON-RPC? [closed]
...ents:
Clients are required to know procedure names;
Procedure parameters order, types and count matters. It's not that easy to change procedure signatures(number of arguments, order of arguments, argument types etc...) on server side without breaking client implementations;
RPC style doesn't expos...
Are Exceptions in C++ really slow
...l, mostly regardless of language, the two basic language features that are orders of magnitude slower than the rest, because they translate to calls of routines that handle complex data structures, are
exception throwing, and
dynamic memory allocation.
Happily in C++ one can often avoid both in ...
Why does X[Y] join of data.tables not allow a full outer join, or a left join?
...n of X[Y]
le <- Y[X]
mallx <- merge(X, Y, all.x = T)
# the column order is different so change to be the same as `merge`
setcolorder(le, names(mallx))
identical(le, mallx)
# [1] TRUE
If you want a full outer join
# the unique values for the keys over both data sets
unique_keys <- uniq...
What optimizations can GHC be expected to perform reliably?
... also explains the passes fairly well. This page explains the optimization ordering, though, like the majority of the Trac Wiki, it is out of date.
For specifics, the best thing to do is probably to look at how a specific program is compiled. The best way to see which optimizations are being perfor...
What is a stack trace, and how can I use it to debug my application errors?
...if(dog == null || dog.firstName == null) return;
The above is the proper order to check for nulls, we start with the base object, dog in this case, and then begin walking down the tree of possibilities to make sure everything is valid before processing. If the order were reversed a NPE could pote...
Efficient Algorithm for Bit Reversal (from MSB->LSB to LSB->MSB) in C
... this on a 32-bit int, just reverse the bits in each byte, and reverse the order of the bytes. That is:
unsigned int toReverse;
unsigned int reversed;
unsigned char inByte0 = (toReverse & 0xFF);
unsigned char inByte1 = (toReverse & 0xFF00) >> 8;
unsigned char inByte2 = (toReverse &am...
onActivityResult() & onResume() [duplicate]
...e Hackborn explains that onActivityResult() is called before onResume() in order to allow anything that might affect the UI to be received and available prior to updating the UI (presumably to avoid a double-update - once in onResume() without the returned result, and then in onActivityResult(), add...
XPath: How to select elements based on their value?
...
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Naming cookies - best practices [closed]
...l three global arrays (!), with precedence depending on how your variables_order setting is set in php.ini. In other words, if you have a _COOKIE named "x" and a querystring param named "x", and you ask for $_REQUEST["x"], you get the cookie value when you might want/expect the GET param. This is es...