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Git/GitHub can't push to master
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244
GitHub doesn't support pushing over the Git protocol, which is indicated by your use of the UR...
Drop unused factor levels in a subsetted data frame
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429
All you should have to do is to apply factor() to your variable again after subsetting:
> s...
Git ignore sub folders
...wildcards?
Solution/*/bin/Debug
Solution/*/bin/Release
With version 1.8.2 of git, you can also use the ** wildcard to match any level of subdirectories:
**/bin/Debug/
**/bin/Release/
share
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im...
Difference between Covariance & Contra-variance
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268
The question is "what is the difference between covariance and contravariance?"
Covariance an...
What is the Invariant Culture?
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132
The invariant culture is a special culture which is useful because it will not change. The curre...
Missing file warnings showing up after upgrade to Xcode 4
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21 Answers
21
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Rename column SQL Server 2008
I am using SQL Server 2008 and Navicat. I need to rename a column in a table using SQL.
11 Answers
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select * vs select column
If I just need 2/3 columns and I query SELECT * instead of providing those columns in select query, is there any performance degradation regarding more/less I/O or memory?
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What are the differences between Rust's `String` and `str`?
... one can only handle it behind a pointer. This means that str most commonly2 appears as &str: a reference to some UTF-8 data, normally called a "string slice" or just a "slice". A slice is just a view onto some data, and that data can be anywhere, e.g.
In static storage: a string literal "foo" ...