[MRG + 1] Add conventions section to userguide. #4508

[cangermueller]

Adds conventions section with two subsections about a) type casting and b) updating model parameters to quick-start userguide. See #4508.

[amueller]

Thanks, this looks good.
One addition I'd like to include is that classifiers can take arbitrary objects as labels and will reproduce them.
so you can do

SVC().fit(iris.data, iris.target_names[iris.targets])
and the predictions will be the string target names.

a little git side-note: please don't merge master into your branch. if you want to update your branch,

git checkout master
git pull upstream master
git checkout feature-branch
git rebase master

I hope we add that to the docs in #3912.

Thanks :)

[amueller]

btw, have you tried building the docs and a) does it look good b) does sphinx throw any errors / warnings [related to this part]?

[cangermueller]

I pointed out that classification targets are preserved. I used doctest to test the documentation and checked if everythinks looks nice.

Thanks for you hint to use rebase instead of merge!

[amueller]

Thanks, looks good to me.

[ogrisel]

Please use a PRNG instance to make the execution deterministic.

>>> rng = np.random.RandomState(0)
>>> X = rng.rand(100, 10)
>>> y = rng.binomial(1, 0.5, 100)
>>> XX = rng.rand(5, 10)

[ogrisel]

Maybe also rename XX to X_new or X_test to be more explicit.

[ogrisel]

This is causing the test to fail on old versions of Python. To avoid that we could do:

>>> predicted = clf.predict(iris.data[:3])
>>> list(predicted)
['setosa', 'setosa', 'setosa']

[ogrisel]

@cangermueller also please try to avoid merging master into a feature / bugfix branch as it makes it hard to rebase and squash intermediate commits later.

Ideally it would be great to start branch again off of current master, git cherry-pick the commits that are not merge commit from this branch, squash them all to a single commit and then push -f the result of that operation to cangermueller 4508 to update this PR.

[ogrisel]

If you are new to squashing stuff, copy your local repo to make a backup.

[amueller]

Travis is failing because of Python2/Python3 string encoding types. Use +ELLIPSES

[cangermueller]

I incorporated your comments. However, I had to create a new branch to rebase master (#4594). The next time I know how to do it properly ;-).

[lesteve]

Basically for the reasons Olivier mentioned above, you don't want any merge commits, i.e. commits with messages like "Merge ...", in your PR branch. Note that your alternative PR still has the same problem.

Something that should work:

# rename your current feature branch in case something goes wrong
git branch -m 4508 4508_bak

# update local master
git checkout master
git pull upstream master

# Create a new feature branch and cherry-pick meaningful commits
# Note that 6df4eac has already been merged into master
git checkout -b 4508
git cherry-pick 6035c98
git cherry-pick 5831524
git cherry-pick 234be23

# force-push into your PR branch
git push origin 4508 -f

If the "Merge ..." commits disappear from the PR and you win ! You should double-check whether all the changes you wanted to make are still there to make sure that you didn't forget to cherry-pick any commits.

[amueller]

pushed as 0fe613e

[ogrisel]

I think you need to git branch -D 4508 just before the git checkout -b:

# rename your current feature branch in case something goes wrong
git branch -m 4508 4508_bak

# update local master
git checkout master
git pull upstream master

# Delete the '4508' branch: the code there will still be available under
# the branch 4508_bak if you need it.
git branch -D 4508

# Create a new feature branch and cherry-pick meaningful commits
# Note that 6df4eac has already been merged into master
git checkout -b 4508
git cherry-pick 6035c98
git cherry-pick 5831524
git cherry-pick 234be23

# force-push into your PR branch
git push origin 4508 -f

[ogrisel]

Thanks @cangermueller and @amueller !

[lesteve]

I think you need to git branch -D 4508 just before the git checkout -b:

Not that this is really important, but git branch -m should have renamed (rather than copied) the 4508 branch so the git checkout -b 4508 should work fine.