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Does Python support short-circuiting?
...circuiting "executed" not printed
1
>>> 1 and fun(1) # fun(1) called and "executed" printed
executed
1
>>> 0 and fun(1) # due to short-circuiting "executed" not printed
0
Note: The following values are considered by the interpreter to mean false:
False None ...
“Large data” work flows using pandas
... one contains different fields, or do they have some records per file with all of the fields in each file?
Do you ever select subsets of rows (records) based on criteria (e.g. select the rows with field A > 5)? and then do something, or do you just select fields A, B, C with all of the records (a...
Using @property versus getters and setters
...
Prefer properties. It's what they're there for.
The reason is that all attributes are public in Python. Starting names with an underscore or two is just a warning that the given attribute is an implementation detail that may not stay the same in future versions of the code. It doesn't preven...
Using generic std::function objects with member functions in one class
...
A non-static member function must be called with an object. That is, it always implicitly passes "this" pointer as its argument.
Because your std::function signature specifies that your function doesn't take any arguments (<void(void)>), you must bind the ...
Swift Beta performance: sorting arrays
...t))
// [-1, 0, 2, 2, 5, 8, 1234]
// [-1, 0, 2, 2, 5, 8, 1234]
Both are called in the same program as written.
var x_swift = CInt[](count: n, repeatedValue: 0)
var x_c = CInt[](count: n, repeatedValue: 0)
for var i = 0; i < n; ++i {
x_swift[i] = CInt(random())
x_c[i] = CInt(random())
}...
Django select only rows with duplicate field values
... syntax is also how Django interprets you wanting to do a join. So, essentially when you try to filter on that, Django thinks you're trying to do a join with count which obviously doesn't exist. The fix is to specify a name for your annotation result, i.e. annotate(mycount=Count('id')) and then filt...
Detect network connection type on Android
...twork is connected and fast enough to meet your demands you have to handle all the network types returned by getSubType().
It took me an hour or two to research and write this class to do just exactly that, and I thought I would share it with others that might find it useful.
Here is a Gist of the...
How do I include a pipe | in my linux find -exec command?
...ld result in only a single agrep process being spawned which would process all the output produced by numerous invocations of zcat.
If you for some reason would like to invoke agrep multiple times, you can do:
find . -name 'file_*' -follow -type f \
-printf "zcat %p | agrep -dEOE 'grep'\n" | s...
How to open a URL in a new Tab using JavaScript or jQuery? [duplicate]
How to open a URL in new tab instead of new window programatically?
6 Answers
6
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How are Python's Built In Dictionaries Implemented?
...e).
Python dictionaries are implemented as hash tables.
Hash tables must allow for hash collisions i.e. even if two distinct keys have the same hash value, the table's implementation must have a strategy to insert and retrieve the key and value pairs unambiguously.
Python dict uses open addressin...