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TypeError: 'dict_keys' object does not support indexing
...keys object behaves a lot more like just the keys half of a dict. Specifically, they support O(1) membership testing (and other set-like methods that can be implemented efficiently on top of that fact). These things aren't possible with a list and if you want a list of the dict's keys, you've alwa...
Ruby, Difference between exec, system and %x() or Backticks
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system
The system method calls a system program. You have to provide the command as a string argument to this method. For example:
>> system("date")
Wed Sep 4 22:03:44 CEST 2013
=> true
The invoked program will use the current STDIN, STDO...
Android LinearLayout Gradient Background
...the colors and it did not work for me. Once I got the alpha channel set it all worked!
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SELECT DISTINCT on one column
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this is really useful case in any various duplication thank you
– ASLIM
Jan 13 at 8:08
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Compare two data.frames to find the rows in data.frame 1 that are not present in data.frame 2
...<- data.frame(a = 1:3, b = letters[1:3])
comparison <- compare(a1,a2,allowAll=TRUE)
comparison$tM
# a b
#1 1 a
#2 2 b
#3 3 c
The function compare gives you a lot of flexibility in terms of what kind of comparisons are allowed (e.g. changing order of elements of each vector, changing order a...
Android - custom UI with custom attributes
...="dimension"/>
</declare-styleable>
</resources>
Basically you have to set up one <declare-styleable /> for your view that contains all your custom attributes (here just one). I never found a full list of possible types, so you need to look at the source for one I guess. T...
React.js - input losing focus when rerendering
I am just writing to text input and in onChange event i call setState , so React rerenders my UI. The problem is that the text input always lose a focus, so i need focus it again for each letter :D.
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Configuring user and password with Git Bash
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I cannot use SSH because of internal firewall rules (don't ask...) Is there another way to let git login automatically?
– Jorn
Apr 20 '15 at 9:04
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Split string every nth character?
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This is a really great answer because its not convoluted in any way and that fact allows you to remember the method easily due to its simplicity
– Trevor Rudolph
Feb 26 '14 at 0:22
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Getting attribute using XPath
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you can use:
(//@lang)[1]
these means you get all attributes nodes with name equal to "lang" and get the first one.
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