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Python list subtraction operation
...] gives [1,1] So it is not really list substraction, it is more like "List from List X without elements from set Y".
– Alfred Zien
Feb 6 '16 at 10:25
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What is the difference between indexOf() and search()?
...rgument
str.indexOf('k') // 3
str.indexOf('k',4) // 11 (it start search from 4th position)
special in search()
search value can be regular expression
str.search('book') // 8
str.search(/book/i) // 0 ( /i =case-insensitive (Book == book)
reference
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Background image jumps when address bar hides iOS/Android/Mobile Chrome
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EDIT: While the above script works perfectly for keeping the background from resizing, it causes a noticeable gap when users scroll down. This is because it is keeping the background sized to 100% of the screen height minus the URL bar. If we add 60px to the height, as swiss suggests, this proble...
How do I update all my CPAN modules to their latest versions?
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An alternative method to using upgrade from the default CPAN shell is to use cpanminus and cpan-outdated.
These are so easy and nimble to use that I hardly ever go back to CPAN shell. To upgrade all of your modules in one go, the command is:
cpan-outdated -p | c...
Check if at least two out of three booleans are true
...e a&&b || b&&c || a&&c version wins then.
Results from Tofubeer with the latest code running OS X:
a&&b || b&&c || a&&c : 1358 ms
a ? b||c : b&&c : 1187 ms
a&b | b&c | c&a : 410 ms
a + b + c >= 2 : 602 ms
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How to detect if multiple keys are pressed at once using JavaScript?
...g for optimization. This is because the script tag blocks further elements from loading until its script is finished downloading. Putting it ahead of the content allows the content to load beforehand.
B (which is where your interest lies) You can check for one or more keys at a time where /*insert c...
How do I escape ampersands in batch files?
How do I escape ampersands in a batch file (or from the
Windows command line) in order to use the start command to
open web pages with ampersands in the URL?
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What is reflection and why is it useful?
...methods which are marked or work in a certain way is still common.
Update from a comment:
The ability to inspect the code in the system and see object types is
not reflection, but rather Type Introspection. Reflection is then the
ability to make modifications at runtime by making use of
i...
Python dictionary: Get list of values for list of keys
...t, mykeys)
Alternatively, using operator.itemgetter can return a tuple:
from operator import itemgetter
myvalues = itemgetter(*mykeys)(mydict)
# use `list(...)` if list is required
Note: in Python3, map returns an iterator rather than a list. Use list(map(...)) for a list.
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What do (lambda) function closures capture?
...estion: You could use partial in the functools module.
With importing add from operator as Chris Lutz proposed the example becomes:
from functools import partial
from operator import add # add(a, b) -- Same as a + b.
adders = [0,1,2,3]
for i in [0,1,2,3]:
# store callable object with first ...