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Use C++ with Cocoa Instead of Objective-C?
...o port my small Ogre3D application, seems VERY painful. Is apple trying to convert everyone to Objc, or is this really a feature ?
– jokoon
Feb 7 '13 at 19:06
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...
What is an undefined reference/unresolved external symbol error and how do I fix it?
...rsal-character-name
in a character literal or a non-raw string literal, is converted to
the corresponding member of the execution character set; [SNIP]
Adjacent string literal tokens are concatenated.
White-space characters separating tokens are no longer significant. Each preprocessing token is con...
Get final URL after curl is redirected
...done < all_videos_link.txt
Results:
real 1m40.832s
user 0m9.266s
sys 0m15.375s
2. Without follow location
time while read -r line; do
curl -kIs -w "%{redirect_url}\n" -o /dev/null $line
done < all_videos_link.txt
Results:
real 0m51.037s
user 0m5.297s
sys 0m8.094s
...
How to Compare Flags in C#?
...
public static bool IsSet( this Enum input, Enum matchTo )
{
return ( Convert.ToUInt32( input ) & Convert.ToUInt32( matchTo ) ) != 0;
}
Then you can do:
FlagTests testItem = FlagTests.Flag1 | FlagTests.Flag2;
if( testItem.IsSet ( FlagTests.Flag1 ) )
//Flag1 is set
Incidentally t...
Is there a Max function in SQL Server that takes two values like Math.Max in .NET?
... @val2))
Edit: If you're dealing with very large numbers you'll have to convert the value variables into bigint in order to avoid an integer overflow.
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How to create module-wide variables in Python? [duplicate]
...f for the current module instead of the current instance !
# db.py
import sys
# this is a pointer to the module object instance itself.
this = sys.modules[__name__]
# we can explicitly make assignments on it
this.db_name = None
def initialize_db(name):
if (this.db_name is None):
# a...
What is “lifting” in Scala?
...e, suppose you have a function which returns an IO[Stream[A]]. This can be converted to the monad transformer StreamT[IO, A]. Now you may wish to "lift" some other value an IO[B] perhaps to that it is also a StreamT. You could either write this:
StreamT.fromStream(iob map (b => Stream(b)))
Or ...
How to restore to a different database in sql server?
...Timeline to access the Backup
Timeline dialog box to manually select a point in time to stop the
recovery action.
In the Backup sets to restore grid, select the backups to restore. This grid displays the backups available for the specified
location. By default, a recovery plan is suggested....
How to convert index of a pandas dataframe into a column?
This seems rather obvious, but I can't seem to figure out how to convert an index of data frame to a column?
7 Answers
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SQL query to group by day
...
actually this depends on what DBMS you are using but in regular SQL convert(varchar,DateColumn,101) will change the DATETIME format to date (one day)
so:
SELECT
sum(amount)
FROM
sales
GROUP BY
convert(varchar,created,101)
the magix number 101 is what date format it is con...