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Replace console output in Python
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An easy solution is just writing "\r" before the string and not adding a newline; if the string never gets shorter this is sufficient...
sys.stdout.write("\rDoing thing %i" % i)
sys.stdout.flush()
Slightly more sophisticated is a progress bar... this is something I am using:
d...
How to populate/instantiate a C# array with a single value?
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i++ copies i, increments i, and returns the original value. ++i just returns the incremented value. Therefore ++i is faster, which can be significant in large loops like we're talking about here.
– tenpn
Nov 8 '12 ...
Test if lists share any items in python
... ways to test if two lists a and b share any items. The first option is to convert both to sets and check their intersection, as such:
bool(set(a) & set(b))
Because sets are stored using a hash table in Python, searching them is O(1) (see here for more information about complexity of operator...
When is SQLiteOpenHelper onCreate() / onUpgrade() run?
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SQLiteOpenHelper onCreate() and onUpgrade() callbacks are invoked when the database is actually opened, for example by a call to getWritableDatabase(). The database is not opened when the database helper object itself is created.
SQLiteOpenHelper versi...
When should I use the HashSet type?
I am exploring the HashSet<T> type, but I don't understand where it stands in collections.
11 Answers
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What is the fastest integer division supporting division by zero no matter what the result is?
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Inspired by some of the comments I got rid of the branch on my Pentium and gcc compiler using
int f (int x, int y)
{
y += y == 0;
return x/y;
}
The compiler basically recognizes that it can use a condition flag of the test in the addition.
As per request the assembly:
.globl...
Best way to select random rows PostgreSQL
I want a random selection of rows in PostgreSQL, I tried this:
12 Answers
12
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How to pass “Null” (a real surname!) to a SOAP web service in ActionScript 3
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}
When currentChild.appendChild is passed the string "null", it first converts it to a root XML element with text null, and then tests that element against the null literal. This is a weak equality test, so either the XML containing null is coerced to the null type, or the null type is coerced ...
When should I use a struct instead of a class?
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MSDN has the answer:
Choosing Between Classes and Structures.
Basically, that page gives you a 4-item checklist and says to use a class unless your type meets all of the criteria.
Do not define a structure unless the
type has all of the following
characterist...
What is the real overhead of try/catch in C#?
So, I know that try/catch does add some overhead and therefore isn't a good way of controlling process flow, but where does this overhead come from and what is it's actual impact?
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