update Readme

R-package/README.md

@@ -14,6 +14,8 @@ Note: 32-bit R/Rtools is not supported.
 
 Installing [Rtools](https://cran.r-project.org/bin/windows/Rtools/) is mandatory, and only support the 64-bit version.
 
+[cmake](https://cmake.org/) must be version 3.8 or higher. 
+
 The default compiler is Visual Studio (or [MS Build](https://www.visualstudio.com/downloads/#build-tools-for-visual-studio-2017)) in Windows. You also can use [MinGW64](https://sourceforge.net/projects/mingw-w64/files/Toolchains%20targetting%20Win64/Personal%20Builds/mingw-builds/) (x86_64-posix-seh) to compile by setting `use_mingw` to `TRUE` in `R-package/src/install.libs.R`. For MinGW users who wants to install online, please check the end of this document for installation using a helper package ([Laurae2/lgbdl](https://github.com/Laurae2/lgbdl/)).
 
 It is recommended to use *Visual Studio* for its better multi-threading efficency in Windows for many core systems. For very simple systems (dual core computers or worse), MinGW64 is recommended for maximum performance. If you do not know what to choose, it is recommended to use [Visual Studio](https://www.visualstudio.com/downloads/#build-tools-for-visual-studio-2017).

python-package/README.rst

@@ -21,30 +21,36 @@ Install from pip
 
 Install `wheel <http://pythonwheels.com>`_ via ``pip install wheel`` first. For windows user, `VC runtime <https://go.microsoft.com/fwlink/?LinkId=746572>`_ is needed if Visual Studio(2015 or 2017) is not installed.
 
-Install from wheel package:
 
 ``pip install lightgbm``
 
-Install from source package:
+
+Install source package from pip
+*******************************
 
 ``pip install --no-binary :all: lightgbm``
 
-Note: Installation from source package require installing `cmake <https://cmake.org/>`_ first, and Visual Studio (or `MS Build <https://www.visualstudio.com/downloads/#build-tools-for-visual-studio-2017>`_) is needed in Windows.
 
-Install GPU version
+Note: Installation from source package require installing `cmake <https://cmake.org/>`_ first.
+
+For Windows user, Visual Studio (or `MS Build <https://www.visualstudio.com/downloads/#build-tools-for-visual-studio-2017>`_) is needed, and `cmake <https://cmake.org/>`_ must be version 3.8 or higher.
+
+Install GPU version:
 
 ``pip install lightgbm --install-option=--gpu``
 
 Note: Boost and OpenCL are needed: details for installation can be found in `gpu-support <https://github.com/Microsoft/LightGBM/wiki/Installation-Guide#with-gpu-support>`_. Need to add OpenCL_INCLUDE_DIR to PATH and export BOOST_ROOT before installation.
 
-Install with MinGW on Windows
+Install with MinGW on Windows:
 
 ``pip install lightgbm --install-option=--mingw``
 
 Install from GitHub
 '''''''''''''''''''
 
-Installation from GitHub require installing `cmake <https://cmake.org/>`_ first, and Visual Studio (or `MS Build <https://www.visualstudio.com/downloads/#build-tools-for-visual-studio-2017>`_) is needed in Windows.
+Installation from GitHub require installing `cmake <https://cmake.org/>`_ first. 
+
+For Windows user, Visual Studio (or `MS Build <https://www.visualstudio.com/downloads/#build-tools-for-visual-studio-2017>`_) is needed, and `cmake <https://cmake.org/>`_ must be version 3.8 or higher.
 
 .. code:: sh