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How to compare two colors for similarity/difference
...t;/b> pctDiffRed = diffRed / 255; is going to give you 0 unless you cast to a float somewhere. <b>2</b> You'll need to multiply by 100 somewhere to get a percentage.
– vaughandroid
Jan 26 '12 at 12:34
...
How to speed up insertion performance in PostgreSQL
...h statement using SQLSetConnectAttr(conn, SQL_ATTR_AUTOCOMMIT, reinterpret_cast<SQLPOINTER>(SQL_AUTOCOMMIT_OFF), 0);
Once all rows have been inserted, commit the transaction using SQLEndTran(SQL_HANDLE_DBC, conn, SQL_COMMIT);. There is no need to explicitly open a transaction.
Unfortunately,...
How to check if a database exists in SQL Server?
...8))
RETURNS bit
AS
BEGIN
declare @result bit = 0
SELECT @result = CAST(
CASE WHEN db_id(@dbname) is not null THEN 1
ELSE 0
END
AS BIT)
return @result
END
GO
Now you can use it like this:
select [dbo].[DatabaseExists]('master') --returns 1
select [dbo].[...
How does Windows 8 Runtime (WinRT / Windows Store apps / Windows 10 Universal App) compare to Silver
...at is used to create Metro style apps. I know you can use it with XAML and it is based on .NET so C# and VB.NET can be used to write the apps, but then it seems to have something to do with HTML, CSS, DOM, and JavaScript.
...
Python: How would you save a simple settings/config file?
...n the file format required.
ConfigParser [.ini format]
I would use the standard configparser approach unless there were compelling reasons to use a different format.
Write a file like so:
# python 2.x
# from ConfigParser import SafeConfigParser
# config = SafeConfigParser()
# python 3.x
from co...
How do I check if a list is empty?
... Part 1
The "pythonic" way fails with NumPy arrays because NumPy tries to cast the array to an array of bools, and if x tries to evaluate all of those bools at once for some kind of aggregate truth value. But this doesn't make any sense, so you get a ValueError:
>>> x = numpy.array([0,1]...
JavaFX and OpenJDK
...
JavaFX is part of OpenJDK
The JavaFX project itself is open source and is part of the OpenJDK project.
Update Dec 2019
For current information on how to use Open Source JavaFX, visit https://openjfx.io. This includes instructions on using JavaFX as a modular library accessed from an exist...
Difference between decimal, float and double in .NET?
...a double/float.
Decimals and Floats/Doubles cannot be compared without a cast whereas Floats and Doubles can. Decimals also allow the encoding or trailing zeros.
float flt = 1F/3;
double dbl = 1D/3;
decimal dcm = 1M/3;
Console.WriteLine("float: {0} double: {1} decimal: {2}", flt, dbl, dcm);
Res...
How to strip all non-alphabetic characters from string in SQL Server?
...nstead of NVARCHAR within his function otherwise, your system will need to cast the string values from VARCHAR to NVARCHAR before it can perform the function which is more expensive. Even with those changes your function still might be faster, but those are a few examples I can see where his functi...
What is the proper declaration of main?
... signature of the main function in C++? What is the correct return type, and what does it mean to return a value from main ? What are the allowed parameter types, and what are their meanings?
...