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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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SQL how to increase or decrease one for a int column in one command
... x=1, y=2
They both can handle your question. However, the first syntax allows for more flexibility to update the record rather than just replace it (as the second one does).
Keep in mind that for both to exist, there has to be a UNIQUE key defined...
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How to use GNU Make on Windows?
I installed MinGW and MSYS, added C:\MinGW\bin to PATH but I still can't run Makefile on Windows' cmd . I would like to run cmd.exe and there type, for example, make all but my cmd says that there is no such command.
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Why am I getting 'Assembly '*.dll' must be strong signed in order to be marked as a prerequisite.'?
...sue.
NuGet
With NuGet it's easy to get into this situation if:
You install a package to one project in your solution.
A new version of that package is deployed to the package source.
You install it to another project in the same solution.
This results in two projects in your solution referenci...
Insert an element at a specific index in a list and return the updated list
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l.insert(index, obj) doesn't actually return anything. It just updates the list.
As ATO said, you can do b = a[:index] + [obj] + a[index:].
However, another way is:
a = [1, 2, 4]
b = a[:]
b.insert(2, 3)
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