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List comprehension: Returning two (or more) items for each item
...>>> list(chain.from_iterable((f(x), g(x)) for x in range(3)))
[2, 0, 3, 1, 4, 4]
Timings:
from timeit import timeit
f = lambda x: x + 2
g = lambda x: x ** 2
def fg(x):
yield f(x)
yield g(x)
print timeit(stmt='list(chain.from_iterable((f(x), g(x)) for x in range(3)))',
...
Is there a way to instantiate objects from a string holding their class name?
...Map()->find(s);
if(it == getMap()->end())
return 0;
return it->second();
}
protected:
static map_type * getMap() {
// never delete'ed. (exist until program termination)
// because we can't guarantee correct destruction order
if(!...
Loop backwards using indices in Python?
I am trying to loop from 100 to 0. How do I do this in Python?
15 Answers
15
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Maximum number of threads in a .NET app?
...ate: Just out of interest: .NET Thread Pool default numbers of threads:
1023 in Framework 4.0 (32-bit environment)
32767 in Framework 4.0 (64-bit environment)
250 per core in Framework 3.5
25 per core in Framework 2.0
(These numbers may vary depending upon the hardware and OS)]
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Is using Random and OrderBy a good shuffle algorithm?
...
209
It's not a way of shuffling that I like, mostly on the grounds that it's O(n log n) for no good...
Any reason why scala does not explicitly support dependent types?
... Bar }
defined class Foo
scala> val foo1 = new Foo
foo1: Foo = Foo@24bc0658
scala> val foo2 = new Foo
foo2: Foo = Foo@6f7f757
scala> implicitly[foo1.Bar =:= foo1.Bar] // OK: equal types
res0: =:=[foo1.Bar,foo1.Bar] = <function1>
scala> implicitly[foo1.Bar =:= foo2.Bar] // Not O...
What is the difference between customErrors and httpErrors?
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edited Jun 20 at 9:12
Community♦
111 silver badge
answered Mar 19 '10 at 23:08
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How to export collection to CSV in MongoDB?
...
UPDATE:
This commit: https://github.com/mongodb/mongo-tools/commit/586c00ef09c32c77907bd20d722049ed23065398 fixes the docs for 3.0.0-rc10 and later. It changes
Fields string `long:"fields" short:"f" description:"comma separated list of field names, e.g. -f name,age"`
to
Fields string `long:"...
Padding characters in printf
...ength of the second string if you want ragged-right lines.
pad=$(printf '%0.1s' "-"{1..60})
padlength=40
string2='bbbbbbb'
for string1 in a aa aaaa aaaaaaaa
do
printf '%s' "$string1"
printf '%*.*s' 0 $((padlength - ${#string1} - ${#string2} )) "$pad"
printf '%s\n' "$string2"
str...
Executing elements inserted with .innerHTML
...
20 Answers
20
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