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What exactly are late static bindings in PHP?
...s in the PHP manual. However, I'll try to give you a quick summary.
Basically, it boils down to the fact that the self keyword does not follow the same rules of inheritance. self always resolves to the class in which it is used. This means that if you make a method in a parent class and call it ...
How to execute a raw update sql with dynamic binding in rails
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It doesn't look like the Rails API exposes methods to do this generically. You could try accessing the underlying connection and using it's methods, e.g. for MySQL:
st = ActiveRecord::Base.connection.raw_connection.prepare("update table set f1=? where f2=? and f3=?")
st.execute(f1, f2, f3)
st...
What does the exclamation mark mean in a Haskell declaration?
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It's a strictness declaration. Basically, it means that it must be evaluated to what's called "weak head normal form" when the data structure value is created. Let's look at an example, so that we can see just what this means:
data Foo = Foo Int Int !Int !(May...
How to smooth a curve in the right way?
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I prefer a Savitzky-Golay filter. It uses least squares to regress a small window of your data onto a polynomial, then uses the polynomial to estimate the point in the center of the window. Finally the window is shifted forward by one data point and the process repeats. This continues until ever...
Converting strings to floats in a DataFrame
...newer version of pandas (0.17 and up), you can use to_numeric function. It allows you to convert the whole dataframe or just individual columns. It also gives you an ability to select how to treat stuff that can't be converted to numeric values:
import pandas as pd
s = pd.Series(['1.0', '2', -3])
p...
Kill child process when parent process is killed
...plication dies, you are still left with child processes running. What we really want is for the child processes to die as soon as the main process dies.
The solution is to use "job objects" http://msdn.microsoft.com/en-us/library/ms682409(VS.85).aspx.
The idea is to create a "job object" for your ...
what is the difference between OLE DB and ODBC data sources?
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Actually sometimes OLE DB wraps the ODBC driver, sometimes it doesn't. See here
– bobobobo
Apr 11 '12 at 2:42
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Literal suffix for byte in .NET?
...e var, you can always cast the byte as in var y = (byte) 5
Although not really related, in C#7, a new binary prefix was introduced 0b, which states the number is in binary format. Still there is no suffix to make it a byte though, example:
var b = 0b1010_1011_1100_1101_1110_1111; //int
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How can I detect the encoding/codepage of a text file
...itively Must Know About Unicode and Character Sets (No Excuses!).
Specifically Joel says:
The Single Most Important Fact About Encodings
If you completely forget everything I just explained, please remember one extremely important fact. It does not make sense to have a string without knowi...
How should I store GUID in MySQL tables?
... I could do the same thing in 4 bytes with an Integer. Since he put that challenge out there to me I thought now was a good time to mention it. That being said...
You can store a guid as a CHAR(16) binary if you want to make the most optimal use of storage space.
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