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How to rename a single column in a data.frame?

...r.name' This code pretty much does the following: names(df) looks into all the names in the df [names(df) == old.var.name] extracts the variable name you want to check <- 'new.var.name' assigns the new variable name. ...
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How to install a specific version of a ruby gem?

Using the command-line gem tool, how can I install a specific version of a gem? 6 Answers ...
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What does ':' (colon) do in JavaScript?

... var o = { r: 'some value', t: 'some other value' }; is functionally equivalent to var o = new Object(); o.r = 'some value'; o.t = 'some other value'; share | improve this answer ...
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Is it safe to resolve a promise multiple times?

... rejected), that is it for a defered object - it is done. If you should call then(...) on it's promise again, you should immediately get the (first) resolved/rejected result. Additional calls to resolve() will not (should not?) have any effect. Not sure what happens if you attempt to reject a de...
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What is an application binary interface (ABI)?

...but the API does not, then the old and new library versions are sometimes called "source compatible". This implies that while a program compiled for one library version will not work with the other, source code written for one will work for the other if re-compiled. For this reason, developers ten...
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What is Scala's yield?

...I use yield instead of map? This map code is equivalent val res = args.map(_.toUpperCase) , right? – Geo Jun 27 '09 at 12:23 4 ...
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Convert Python dict into a dataframe

... The error here, is since calling the DataFrame constructor with scalar values (where it expects values to be a list/dict/... i.e. have multiple columns): pd.DataFrame(d) ValueError: If using all scalar values, you must must pass an index You could ...
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Reintegrate can only be used if revisions X through Y were previously merged from to reintegra

Been using SVN branches with Tortoise 1.6. I've been periodically merging the trunk into the branch to keep it up to date. ...
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Importing CommonCrypto in a Swift framework

...mething a little simpler and more robust is to create an Aggregate target called "CommonCryptoModuleMap" with a Run Script phase to generate the module map automatically and with the correct Xcode/SDK path: The Run Script phase should contain this bash: # This if-statement means we'll only run ...
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Where is the Keytool application?

...achine, you would normally find the jdk at C:\Program Files\Java\jdk1.8.0_121\bin It is used for managing keys and certificates you can sign things with, in your case, probably a jar file. If you provide more details of what you need to do, we could probably give you a more specific answer. ...