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Python - Create a list with initial capacity
...ux
Perhaps you could avoid the list by using a generator instead:
def my_things():
while foo:
#baz
yield bar
#qux
for thing in my_things():
# do something with thing
This way, the list isn't every stored all in memory at all, merely generated as needed.
...
How to step through Python code to help debug issues?
...rSummoner, pudb is great for that. Also pydev
– alpha_989
Jun 11 '18 at 19:45
pdb is not a command line tool. To use i...
Logical operators for boolean indexing in Pandas
...l-and since only x or y can be returned. In contrast, x & y triggers x.__and__(y) and the __and__ method can be defined to return anything we like.
– unutbu
Apr 15 '16 at 22:58
...
How do I execute a string containing Python code in Python?
....stderr = codeErr
exec code
# restore stdout and stderr
sys.stdout = sys.__stdout__
sys.stderr = sys.__stderr__
print f(4)
s = codeErr.getvalue()
print "error:\n%s\n" % s
s = codeOut.getvalue()
print "output:\n%s" % s
codeOut.close()
codeErr.close()
...
Is it possible to declare two variables of different types in a for loop?
...:
auto [vec, i32] = std::tuple{std::vector<int>{3, 4, 5}, std::int32_t{12}}
A specific application of this is iterating over a map, getting the key and value,
std::unordered_map<K, V> m = { /*...*/ };
for (auto& [key, value] : m) {
// ...
}
See a live example here
C++14: ...
Oracle “(+)” Operator
...e a link at the official Oracle documentation: docs.oracle.com/html/A95915_01/sqopr.htm
– Vargan
Jun 3 '15 at 16:55
...
Connection timeout for SQL server
...ng called.
– 3Dave
Nov 29 '10 at 22:06
Not according to this msdn blog post: blogs.msdn.com/b/spike/archive/2008/07/31...
Inline labels in Matplotlib
...0.5,100).
– egpbos
Mar 12 '14 at 13:06
Is there any way to use this without scipy? On my current system it's a pain to...
Code Golf: Lasers
...amp;!ge,$s=$r+=99for<>;%d='>.^1<2v3'=~/./g;($r)=grep$d|=$d{$t{$_}},%t;
{$_=$t{$r+=(1,-99,-1,99)[$d^=3*/\\/+m</>]};/[\/\\ ]/&&redo}die/x/?true:false,$/
The first line loads the input into %t, a table of the board where $t{99*i+j} holds the character at row i,column j. Then...
Python list subtraction operation
...t to use the - infix syntax, you can just do:
class MyList(list):
def __init__(self, *args):
super(MyList, self).__init__(args)
def __sub__(self, other):
return self.__class__(*[item for item in self if item not in other])
you can then use it like:
x = MyList(1, 2, 3, 4...