Merge ef0d773 into 3424afc

docs/sources/CHANGELOG.md

@@ -28,7 +28,8 @@ The CHANGELOG for the current development version is available at
 
 ##### Changes
 
-- Now uses the latest joblib library under the hood for multiprocessing instead of `sklearn.externals.joblib` ([#547](https://github.com/rasbt/mlxtend/pull/547))
+- Now uses the latest joblib library under the hood for multiprocessing instead of `sklearn.externals.joblib`. ([#547](https://github.com/rasbt/mlxtend/pull/547))
+- Changes to `StackingCVClassifier` and `StackingCVRegressor` such that first-level models are allowed to generate output of non-numeric type. ([#562](https://github.com/rasbt/mlxtend/pull/562))
 
 
 ##### Bug Fixes

docs/sources/CONTRIBUTING.md

@@ -16,9 +16,8 @@ and checking off items as you go.
 3. [ ]  Create and check out a new topic branch (please don't make modifications in the master branch)
 4. [ ]  Implement the new feature or apply the bug-fix  
 5. [ ]  Add appropriate unit test functions in `mlxtend/*/tests`
-6. [ ]  Run `nosetests ./mlxtend -sv` and make sure that all unit tests pass  
-7. [ ]  Check/improve the test coverage by running `nosetests ./mlxtend --with-coverage`
-8. [ ]  Check for style issues by running `flake8 ./mlxtend` (you may want to run `nosetests` again after you made modifications to the code)
+6. [ ]  Run `PYTHONPATH='.' pytest ./mlxtend -sv` and make sure that all unit tests pass  
+7. [ ]  Check for style issues by running `flake8 ./mlxtend` (you may want to run `pytest` again after you made modifications to the code)
 8. [ ]  Add a note about the modification/contribution to the `./docs/sources/changelog.md` file  
 9. [ ]  Modify documentation in the appropriate location under `mlxtend/docs/sources/`  
 10. [ ]  Push the topic branch to the server and create a pull request
@@ -164,14 +163,9 @@ Now it's time to modify existing code or to contribute new code to the project.
 Add the respective unit tests and check if they pass:
 
 ```bash
-$ nosetests -sv
+$ PYTHONPATH='.' pytest ./mlxtend ---with-coverage
 ```
 
-Use the `--with-coverage` flag to ensure that all code is being covered in the unit tests:
-
-```bash
-$ nosetests --with-coverage
-```
 
 #### 5. Documenting changes
 

mlxtend/classifier/stacking_cv_classification.py

@@ -208,7 +208,7 @@ def fit(self, X, y, groups=None, sample_weight=None):
             final_cv.random_state = self.random_state
 
         # Input validation.
-        X, y = check_X_y(X, y, accept_sparse=['csc', 'csr'])
+        X, y = check_X_y(X, y, accept_sparse=['csc', 'csr'], dtype=None)
 
         if sample_weight is None:
             fit_params = None

mlxtend/regressor/stacking_cv_regression.py

@@ -164,7 +164,7 @@ def fit(self, X, y, groups=None, sample_weight=None):
             self.regr_ = self.regressors
             self.meta_regr_ = self.meta_regressor
 
-        X, y = check_X_y(X, y, accept_sparse=['csc', 'csr'])
+        X, y = check_X_y(X, y, accept_sparse=['csc', 'csr'], dtype=None)
 
         kfold = check_cv(self.cv, y)
         if isinstance(self.cv, int):