R CMD check issues.Fix C/C++ problems causing R CMD CHECK errors.
melt.data.frame() throws when encountering objectsof typePOSIXlt, and requests a conversion to the (muchsaner)POSIXct type.
melt.data.frame() now properly sets the OBJECT bitonvalue variable generated if attributes are copied (forexample, when multiple POSIXct columns are concatenated to generate thevalue variable) (#50)
melt.data.frame() can meltdata.framescontaininglist elements asid columns.(#49)
melt.data.frame() no longer errors whenmeasure.vars isNULL or empty. (#46)
dcast() andacast() gain a useful errormessage if you usevalue_var intead ofvalue.var (#16), and ifvalue.var doesn’texist (#9). They also work better with. in specificationslike. ~ . orx + y ~ .
melt.array() creates factor variables with levels inthe same order as the original rownames (#19)
melt.data.frame() gains an internal Rcpp / C++implementation, and is now many orders of magnitudes faster. It alsopreserves identical attributes for measure variables, and now throws awarning if they are dropped. (Thanks to Kevin Ushey)
melt.data.frame() gains afactorsAsStrings argument that controls whether factors areconverted to character when melted as measure variables. This isTRUE by default for backward compatibility.
melt.array() gains aas.is argumentwhich can be used to prevent dimnames being converted withtype.convert()
recast() now returns a data frame instead of a list(#45).
Fix incompatibility with plyr 1.8
Fix evaluation bug revealed by knitr. (Fixes #18)
Fixed a bug inmelt where it didn’t automaticallyget variable names when used with tables. (Thanks to WinstonChang)
Fixed bug in melt where factors were converted to integers,instead of to characters
When the measured variable is a factor,dcast nowconverts it to a character rather than throwing an error.acast still returns a factor matrix. (Thanks to BrianDiggs.)
acast is now much faster, due to fixing a very slowway of naming the output. (Thanks to José Bartolomei Díaz for the bugreport)
value_var argument toacast anddcast renamed tovalue.var to be consistentwith other argument names
OrderNA factor levels before(all)when creating margins
Corrected reshape citation.
melt.data.frame no longer turns characters intofactors
All melt methods gain ana.rm andvalue.name arguments - these previously were only possessedbymelt.data.frame (Fixes #5)