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To ternary or not to ternary? [closed]
...ve come across many programmers that are completely against ever using it, and some that use it too often.
54 Answers
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With arrays, why is it the case that a[5] == 5[a]?
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The C standard defines the [] operator as follows:
a[b] == *(a + b)
Therefore a[5] will evaluate to:
*(a + 5)
and 5[a] will evaluate to:
*(5 + a)
a is a pointer to the first element of the array. a[5] is the value that's 5 el...
Wrapping a C library in Python: C, Cython or ctypes?
...Python application. I don't want to wrap the whole API, only the functions and datatypes that are relevant to my case. As I see it, I have three choices:
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What is normalized UTF-8 all about?
... bit identical to the input.
Canonical normalization comes in 2 forms: NFD and NFC. The two are equivalent in the sense that one can convert between these two forms without loss. Comparing two strings under NFC will always give the same result as comparing them under NFD.
NFD
NFD has the characters ...
MySQL SELECT WHERE datetime matches day (and not necessarily time)
...rds, if my table only contained the following 4 records, then only the 2nd and 3rd would be returned if I limit to 2012-12-25.
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What's the difference between hard and soft floating point numbers?
... architecture" This can make sense for a library to be machine-independent and bit-exact (soft float) in accuracy-critical parts and fast (hard float) in parts where small deviations don't matter.
– PhilLab
May 29 '17 at 12:18
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When is memoization automatic in GHC Haskell?
... in foldl' (+) 0 (y ++ [x])
GHC might notice that y does not depend on x and rewrite the function to
f = let y = [1..30000000] in \x -> foldl' (+) 0 (y ++ [x])
In this case, the new version is much less efficient because it will have to read about 1 GB from memory where y is stored, while th...
Most efficient way to store thousand telephone numbers
...digits left. We view these remaining five digits as 17-bit binary integers and store k of those bits using one method and 17 - k = m with a different method, determining k at the end to minimize the required space.
We first sort the phone numbers (all reduced to 5 decimal digits). Then we count how...
How do you track record relations in NoSQL?
I am trying to figure out the equivalent of foreign keys and indexes in NoSQL KVP or Document databases. Since there are no pivotal tables (to add keys marking a relation between two objects) I am really stumped as to how you would be able to retrieve data in a way that would be useful for normal we...
Converting from a string to boolean in Python?
...ref.html#distutils.util.strtobool
True values are y, yes, t, true, on and 1; false values are n, no, f, false, off and 0. Raises ValueError if val is anything else.
Be aware that distutils.util.strtobool() returns integer representations and thus it needs to be wrapped with bool() to get Bool...