ENH: Allow for custom variable/value column names when melt()'ing

[hoechenberger]

ENH, CLN: When melt()'ing, allow for specification of custom variable and value names of the resulting DataFrame. Also fix indentation in melt() example to reflect actual output.

[jreback]

can u add a test and release notes mention (doc string example in v0.11.1 if u want too)
thxs

[jreback]

can you connect travis? see CONTRIBUTING.md for instructions....

and for a couple of the tests can you do something like:

result = melt......
expected = ......
tm.assert_frame_equal(result,expected)

to actually compare values and indicies (in this case its actually important as you are provide
some new functionaility that changes the column names, need to have a test for that)

similar to how test_pairs tests things (but doesn't have to be extensive....just a couple
of cases to make sure that melt is doing what you ask in various scenarios)

e.g. empty frame
incorrect frame
etc..

thanks

[hoechenberger]

Thanks for your helpful feedback! I'm completely new to Python, testing, and Git(hub) :) I will try to improve my contribution. Stay tuned!

[jreback]

@hoechenberger see if you can connect travis on this....thxs

[hoechenberger]

I will look into this tomorrow, thanks! :)

[hoechenberger]

Now I'm wondering whether, as part of a good practice, I should create my test DataFrames manually or via methods from pandas.util.testing? I see both methods used across the pandas testing code...

[jreback]

you do either -

whatever works for testing te feature u r doing
you also might find makeCustomDataFrame useful (in testing as well)
since u r testing reshaping

[hoechenberger]

I think I sort of srewed the branching here. But eventually got things merged back into the master branch. Travis-CI is currently testing the code, I'm excited.

[jreback]

to avoid pulling in the merge to this branch, do this:

git br this_branch --set-upstream master

then

git checkout master
git pull

updates master

git checkout this_branch
git pull --rebase

will pull in any changes w/o creating a merge commit
you might need to fix any conflicts

separately, pls rebase this to 1 or more commits (and you can eliminate the merge commit too)

git checkout this_branch
git rebase -i <commit prior to your branch>

remove the line of the merge branches
you can s to meld commits together

when done

git push origin this_branch -f

will replace all of the commits on this branch with the new ones
(with out the f it appends the newest commits)

[hoechenberger]

Thanks! I think it's finally in a useful shape, no? :)

[jreback]

yes...that looks good.....once travis finishes will merge

thanks

git is an animal...once you tame it, its your friend :)

[hoechenberger]

Great, thanks! I'm crossing my fingers ;)