update pip building, troubleshooting with new makefile, plus friendly error message when fail importing sklearn

python-package/build_trouble_shooting.md

@@ -18,9 +18,12 @@ Linux platform (also Mac OS X in general)
 
 **Solution 0**: Please check if you have:
 
-* installed C++ compilers, for example `g++` and `gcc` (Linux) or `clang LLVM` (Mac OS X). Recommended compilers are `g++-5` or newer (Linux and Mac), or `clang` comes with Xcode in Mac OS X. For installting compilers, please refer to your system package management commands, e.g. `apt-get` `yum` or `brew`(Mac).
+* installed the latest C++ compilers and `make`, for example `g++` and `gcc` (Linux) or `clang LLVM` (Mac OS X). Recommended compilers are `g++-5` or newer (Linux and Mac), or `clang` comes with Xcode in Mac OS X. For installting compilers, please refer to your system package management commands, e.g. `apt-get` `yum` or `brew`(Mac).
 * compilers in your `$PATH`. Try typing `gcc` and see if your have it in your path.
 * Do you use other shells than `bash` and install from `pip`? In some old version of pip installation, the shell script used `pushd` for changing directory and triggering the build process, which may failed some shells without `pushd` command. Please update to the latest version by removing the old installation and redo `pip install xgboost`
+* Some outdated `make` may not recognize the recent changes in the `Makefile` and gives this error, please update to the latest `make`:
+
+    `/usr/lib/ruby/gems/1.8/gems/make-0.3.1/bin/make:4: undefined local variable or method 'make' for main:Object (NameError)`    
 
 **Trouble 1**: I see the same error message in **Trouble 0** when install from `pip install xgboost`.
 
@@ -30,7 +33,7 @@ Linux platform (also Mac OS X in general)
 
     OSError: /home/dmlc/anaconda/lib/python2.7/site-packages/xgboost/./wrapper/libxgboostwrapper.so: invalid ELF header
    
-**Solution 2**: Solution is as in 0 and 1 by installing `g++` compiler. The reason for this rare error is that, `pip` ships with a pre-compiled `libxgboostwrapper.so` with Mac for placeholder for allowing `setup.py` to find the right lib path. If a system doesn't compile, it may refer to this placeholder lib and fail. This placeholder `libxgboostwrapper.so` will be automatically removed and correctly generated by the compiling on-the-fly for the system.
+**Solution 2**: Solution is as in 0 and 1 by installing the latest `g++` compiler and the latest `make`. The reason for this rare error is that, `pip` ships with a pre-compiled `libxgboostwrapper.so` with Mac for placeholder for allowing `setup.py` to find the right lib path. If a system doesn't compile, it may refer to this placeholder lib and fail. This placeholder `libxgboostwrapper.so` will be automatically removed and correctly generated by the compiling on-the-fly for the system.
 
 **Trouble 3**: My system's `pip` says it can't find a valid `xgboost` installation release on `PyPI`.
 **Solution 3**: Some linux system comes with an old `pip` version. Please update to the latest `pip` by following the official installation document at <http://pip.readthedocs.org/en/stable/installing/>

python-package/conv_rst.py

@@ -1,8 +0,0 @@
-# pylint: disable=invalid-name, exec-used
-"""Convert README.md to README.rst for PyPI"""
-
-from pypandoc import convert
-
-read_md = convert('python-package/README.md', 'rst')
-with open('python-package/README.rst', 'w') as rst_file:
-    rst_file.write(read_md)

python-package/setup_pip.py

@@ -34,7 +34,7 @@ LIB_PATH = libpath['find_lib_path']()
 #and be sure to test it firstly using "python setup.py register sdist upload -r pypitest"
 setup(name='xgboost',
       #version=open(os.path.join(CURRENT_DIR, 'xgboost/VERSION')).read().strip(),
-      version='0.4a28',
+      version='0.4a30',
       description=open(os.path.join(CURRENT_DIR, 'README.rst')).read(),
       install_requires=[
           'numpy',

python-package/xgboost/__init__.py

@@ -10,8 +10,11 @@ import os
 
 from .core import DMatrix, Booster
 from .training import train, cv
-from .sklearn import XGBModel, XGBClassifier, XGBRegressor
-from .plotting import plot_importance, plot_tree, to_graphviz
+try:
+    from .sklearn import XGBModel, XGBClassifier, XGBRegressor
+    from .plotting import plot_importance, plot_tree, to_graphviz
+except ImportError:
+    print('Error when loading sklearn/plotting. Please install scikit-learn')
 
 VERSION_FILE = os.path.join(os.path.dirname(__file__), 'VERSION')
 __version__ = open(VERSION_FILE).read().strip()