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Confusion between factor levels and factor labels
There seems to be a difference between levels and labels of a factor in R.
Up to now, I always thought that levels were the 'real' name of factor levels, and labels were the names used for output (such as tables and plots). Obviously, this is not the case, as the following example shows:
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What optimizations can GHC be expected to perform reliably?
...ut I don't know what they all are, nor how likely they are to be performed and under what circumstances.
3 Answers
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Forgot “git rebase --continue” and did “git commit”. How to fix?
...rebasing code in git, I got some merge conflicts. I resolved the conflicts and did:
4 Answers
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navigator.geolocation.getCurrentPosition sometimes works sometimes doesn't
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I have been having exactly the same problem, and finding almost no information online about it. Nothing at all in the books. Finally I found this sober query on stackoverflow and (ha!) it was the final impetus I needed to set up an account here.
And I have a partial an...
MongoDB and “joins” [duplicate]
...ll only be evaluated when needed. A join (in a SQL database) on the other hand will resolve relationships and return them as if they were a single table (you "join two tables into one").
You can read more about DBRef here:
http://docs.mongodb.org/manual/applications/database-references/
There are ...
Integrating MySQL with Python in Windows
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Download page for python-mysqldb. The page includes binaries for 32 and 64 bit versions of for Python 2.5, 2.6 and 2.7.
There's also discussion on getting rid of the deprecation warning.
UPDATE: This is an old answer. Currently, I would recommend using PyMySQL. It's pure python, so it supp...
The input is not a valid Base-64 string as it contains a non-base 64 character
I have a REST service that reads a file and sends it to another console application after converting it to Byte array and then to Base64 string. This part works, but when the same stream is received at the application, it gets manipulated and is no longer a valid Base64 string. Some junk characters ...
Maven: The packaging for this project did not assign a file to the build artifact
I'm using Maven 3.0.3 on Mac 10.6.6. I have a JAR project and when I run the command "mvn clean install:install", I'm getting the error,
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When to use , tag files, composite components and/or custom components?
I started using JSF 2.0 with Facelets recently and got puzzled by new composite components knowing existing <ui:include> and other templating techniques offered by Facelets 1.x.
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Position Relative vs Absolute?
What is the difference between position: relative and position: absolute in CSS? And when should you use them?
10 Answe...