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How do you get the logical xor of two variables in Python?
...e not comparing apples to oranges, is "if xor( isApple(x), isApple(y) )" really clearer than "if isApple(x) != isApple(y)" ? Not to me!
– AmigoNico
May 21 '12 at 18:27
109
...
enum - getting value of enum on string conversion
...>> member.value
1
You could add a __str__ method to your enum, if all you wanted was to provide a custom string representation:
class D(Enum):
def __str__(self):
return str(self.value)
x = 1
y = 2
Demo:
>>> from enum import Enum
>>> class D(Enum):
...
Why not use java.util.logging?
...ojects.
There are objective reasons for preferring SLF4J. For one, SLF4J allows the end-user the liberty to choose the underlying logging framework. In addition, savvier users tend to prefer logback which offers capabilities beyond log4j, with j.u.l falling way behind. Feature-wise j.u.l may be s...
Why should eval be avoided in Bash, and what should I use instead?
...rintln. We could, of course, just redirect the output of println on each call, but for the sake of example, we're not going to do that. We'll need to use eval, since variables can't be used to redirect output.
function println
{
eval printf "$2\n" "${@:3}" $1
}
function error
{
println '...
Extracting bits with a single multiplication
.....
A multiplication is a bunch of shift-and-add operations. The key is to allow overflow to "shift away" the bits we don't need and put the ones we want in the right place.
Multiplication by 4 (00000100) would shift everything left by 2 and get you to a00b0000 . To get the b to move up we need to...
Inserting multiple rows in mysql
...
When loading a table from a text file, use LOAD DATA INFILE. This is usually 20 times faster than using INSERT statements.
Optimizing INSERT Statements
You can find more tips on how to speed up your insert statements on the link above.
...
Positioning MKMapView to show multiple annotations at once
...tations I want to add to my MKMapView (it could 0-n items, where n is generally around 5). I can add the annotations fine, but I want to resize the map to fit all annotations onscreen at once, and I'm not sure how to do this.
...
How to add a progress bar to a shell script?
...}
done
If you already have a loop which does a lot of work, you can call the
following function at the beginning of each iteration to update the
spinner:
sp="/-\|"
sc=0
spin() {
printf "\b${sp:sc++:1}"
((sc==${#sp})) && sc=0
}
endspin() {
printf "\r%s\n" "$@"
}
until wor...
Why should I use document based database instead of relational database?
...obvious answer is you should use it if your data isn't relational. This usually manifests itself in having no easy way to describe your data as a set of columns. A good example is a database where you actually store paper documents, e.g. by scanning office mail. The data is the scanned PDF and you h...
What is an EJB, and what does it do?
...are, what does it mean their instances are managed in a pool, blah blah. Really can't get a good grip of them.
4 Answers
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