原本安装pyflann应该是很简单的一件事，但是似乎作者没有考虑到这些，他用的应该是Ubuntu吧，即不兼容CentOS，也无法在Mac OS上面用。

FLANN

目前最完整的（近似）最近邻开源库。不但实现了一系列查找算法，还包含了一种自动选取最快算法的机制。

FLANN is a library for performing fast approximate nearest neighbor searches in high dimensional spaces.

Mac OS安装flann

方法比较简单。。

brew install flann

或者

sudo port install flann

CentOS安装flann

CentOS安装flann 以及pyflann

yum install flann
yum insall flann-python

但是都存在问题

CentOS pyflann报错

raise ImportError('Cannot load dynamic library. Did you compile FLANN?')
 ImportError: Cannot load dynamic library. Did you compile FLANN?

这个总是好解决，查看一下site-packages下面的flann_ctypes.py就会发现

libnames = ['libflann.so']
libdir = 'lib'
if sys.platform == 'win32':
    libnames = ['flann.dll', 'libflann.dll']
elif sys.platform == 'darwin':
    libnames = ['libflann.dylib']

while root_dir!=None:
    for libname in libnames:
        try:
            #print "Trying ",os.path.join(root_dir,'lib',libname)
            flannlib = cdll[os.path.join(root_dir,libdir,libname)]
            return flannlib
        except Exception:
            pass
        try:
            flannlib = cdll[os.path.join(root_dir,"build",libdir,libname)]
            return flannlib
        except Exception:
            pass
    tmp = os.path.dirname(root_dir)
    if tmp == root_dir:
        root_dir = None
    else:
        root_dir = tmp

库的名字是libflann.so，从/usr/lib下面复制过来

 cp /usr/lib/libflann.so.1.7 /usr/lib/python2.6/site-packages/pyflann/lib

Mac OS pyflann报错

这个问题真心比较坑爹

Mac OS site-packages

查看site-packages路径的方法

Python 2.7.5 (default, Sep 12 2013, 21:33:34)
[GCC 4.2.1 Compatible Apple LLVM 5.0 (clang-500.0.68)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>> import site;
>>> site.getsitepackages();
['/System/Library/Frameworks/Python.framework/Versions/2.7/Extras/lib/python', '/Library/Python/2.7/site-packages']
>>> exit;

所以我们需要cd到这个目录

  cd /Library/Python/2.7/site-packages/pyflann-1.6.11-py2.7.egg/pyflann

遇到这个错误时

  ImportError: No module named bindings.flann_ctypes

需要建个bindings再将flann_ctypes等文件拷贝过去

接着再需要从某个linux机器上，或者从代码中拷贝出io