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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):
...
How to avoid the “divide by zero” error in SQL?
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@Anderson That's not true at all. Are you sure you didn't accidentally use IsNull instead of NullIf? Try it yourself! SELECT Value,1/NullIf(Value,0)FROM(VALUES(0),(5.0),(NULL))x(Value); Unless by "breaks" you mean returns a NULL? You can convert that to ...
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.
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What does the regular expression /_/g mean?
...egex matches the _ character.
The g means Global, and causes the replace call to replace all matches, not just the first one.
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Inserting multiple rows in mysql
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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.
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Extracting bits with a single multiplication
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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...
Mapping over values in a python dictionary
..., f(kv[1])), my_dictionary.iteritems()))
but that's not that readable, really.
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Regular Expressions- Match Anything
...ing something after * (as in /.*(?:)/) or using the regex constructor (var foo = new RegExp(".*")).
– Tim Pietzcker
Oct 24 '18 at 19:11
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How can I remove the string “\n” from within a Ruby string?
... your gsub. The different quote marks behave differently.
Double quotes " allow character expansion and expression interpolation ie. they let you use escaped control chars like \n to represent their true value, in this case, newline, and allow the use of #{expression} so you can weave variables and...
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...